Jwt Attack

Privilege escalation in pac4j-oidc before 6.5.6 allows authenticated attackers to forge Keycloak access tokens and claim arbitrary administrative roles without cryptographic validation. The `KeycloakRolesAuthorizationGenerator` component extracted realm and client role claims directly from access token payloads without verifying signatures, issuers, audiences, or expiration - violating core JWT and OIDC validation requirements. Any application relying on pac4j Keycloak role-based authorization is exposed to full authorization bypass; no public exploit has been identified at time of analysis and the vulnerability is not listed in CISA KEV.

Authentication bypass in the Omnivore API (packages/api) before commit abf53d6 lets a remote unauthenticated attacker impersonate any Apple-linked account through a JWT algorithm-confusion flaw in Apple sign-in. Because decodeAppleToken trusted the attacker-controlled 'alg' header and jsonwebtoken v8 does not enforce key/algorithm compatibility, an attacker can switch the token to HS256 and sign it with Apple's public RSA key used as the HMAC secret. Reported by VulnCheck; no public exploit identified at time of analysis, though the technique is a well-documented class of attack.

Authentication bypass in the WPMU DEV Dashboard WordPress plugin (all versions through 5.0.1) lets an unauthenticated attacker forge a valid administrator session by abusing an HMAC signature-verification flaw in the Hub SSO login flow. Because the signing routine in the unauthenticated wdpsso_step1 action covers a different, unseparated field concatenation than the verifier in wdpsso_step2, an attacker can obtain a legitimately signed token and replay it with fields rearranged to authenticate as admin. No public exploit is identified at time of analysis, but the network-reachable, unauthenticated nature and 9.8 CVSS make this a high-priority patch item.

Cryptographic integrity bypass and weak key derivation in the openssl-encrypt Python package (jahlives) before 1.4.9 let an attacker with physical write access to a portable USB drive plant an undetected root-level autorun payload and precompute the drive encryption key offline. The integrity verifier only checks manifest-listed files, so added files pass verification, while a hard-coded fallback KDF salt (_LEGACY_FIXED_SALT) enables an offline rainbow-table attack against drives lacking a per-drive salt. No public exploit identified at time of analysis, and it is not listed in CISA KEV.

Signature-trust bypass in the openssl_encrypt Python library (PyPI 'openssl-encrypt') versions 1.4.8 and earlier lets an attacker get a forged GPG key enrolled as a plugin-signing trust anchor. Because enroll_trust_key matches key fingerprints with a suffix-tolerant comparison, an operator who verifies only a short (~32-bit, forgeable) GPG key id can be tricked into trusting an attacker-controlled colliding key, which then validly signs malicious plugins even under the strict ENFORCE signature policy. No CISA KEV listing and no public exploit identified at time of analysis; the fix is in 1.4.9.

Arbitrary code execution in jahlives openssl_encrypt before 1.4.9 stems from a flawed plugin trust model that uses a denylist rather than an allowlist to identify built-in plugins, so unsigned plugins dropped into top-level plugins/ directories or unrecognized subdirectories evade signature verification entirely. An attacker who can place a malicious plugin along documented installation paths gains code execution inside the CLI process, exposing user passwords and cryptographic keys. No public exploit identified at time of analysis, and the CVSS 4.0 score is 9.3 (Critical), though the network vector conflicts with the local plugin-placement prerequisite.

Signature verification bypass in openssl_encrypt (the jahlives Python encryption library) before version 1.4.9 lets attackers who possess a revoked or expired-but-formerly-trusted GPG signing key defeat plugin authenticity checks and run malicious code in the host process. The flaw lives in gpg_runner.verify_detached, which treats a VALIDSIG status line as success while ignoring REVKEYSIG, EXPKEYSIG, and gpg's own exit code. No public exploit has been identified at time of analysis, and it is not listed in CISA KEV, but the network-reachable, unauthenticated CVSS 4.0 score of 9.3 marks it as high priority for any deployment that loads signed plugins.

Cryptographic-integrity bypass in the openssl_encrypt file-encryption utility (jahlives) before 1.4.9 lets an attacker edit the header of an envelope-format encrypted file to delete recovery-slot fields without any key and without re-encrypting the payload. Because recovery-slot presence is never cryptographically verified (CWE-347), recovery paths that the owner deliberately added can be silently stripped and the tampering goes undetected. There is no public exploit or CISA KEV listing at time of analysis, and no EPSS score was supplied; the action is trivially performed by anyone able to modify the file, which drives the critical CVSS 4.0 score of 9.3.

Privilege escalation in HP OMEN Gaming Hub prior to version 1101.2608.0.0 allows local attackers holding standard user credentials to gain elevated system access by exploiting improper JWT signature verification (CWE-347). The gaming hub service, which operates with elevated OS privileges to manage hardware performance settings on HP OMEN systems, fails to validate cryptographic signatures on JWT tokens used for internal access control, enabling privilege claim forgery. No public exploit code has been identified at time of analysis, and this vulnerability does not appear in the CISA Known Exploited Vulnerabilities catalog.

SAML authentication bypass in Apache CloudStack 4.20.3.0 and 4.22.1.0 permits a network-positioned attacker to forge SAML responses and authenticate as any user against the management server without valid credentials. The flaw stems from improper cryptographic signature verification (CWE-347): the management server fails to validate SAML response certificates, so a forged assertion passes unchecked. Exploitation requires either spoofing the IdP's IP address or registering a controlled URL as a trusted IdP endpoint in the management server - conditions that raise the practical bar but, if met, yield full administrative access. No public exploit or CISA KEV listing has been identified; the EPSS score of 0.07% reflects minimal observed exploitation at time of analysis.

Privilege elevation in Microsoft Azure Data Factory allows a remote, unauthenticated attacker to gain elevated privileges by exploiting improper verification of a cryptographic signature. Tagged as a JWT/authentication-bypass issue, the flaw lets an attacker forge or tamper with signed tokens that the service fails to validate correctly, defeating access controls over the network. There is no public exploit identified at time of analysis, and the EPSS probability is low (0.28%), but the CVSS 9.8 rating reflects total technical impact if exploited.

Webhook signature bypass in the appwrite/templates github-issue-bot (≤ 1.1.2) allows any unauthenticated network caller to invoke the bot's comment-posting functionality without a valid GitHub HMAC signature. An inverted boolean condition in verifyWebhook causes requests lacking the X-Hub-Signature-256 header to short-circuit to success, so the body is processed as if it were a legitimate GitHub event. With attacker-controlled repository, issue, and author fields passed directly to postComment, the deployment's GITHUB_TOKEN is used to post arbitrary comments on any accessible GitHub repository and issue. No public exploit code is identified at time of analysis.

Authentication bypass and token replay in node-opcua's UserNameIdentityToken handler enables unauthenticated remote attackers to authenticate as any user whose account accepts an empty password, and to replay captured session tokens unconditionally across unrelated sessions. Versions up to and including 2.165.0 of the npm package are affected. The vulnerability is compounded when SecurityMode=None is configured, which causes the channel-level signature verification to return true unconditionally. A proof-of-concept attack sequence has been dynamically confirmed by the reporter; no vendor-released patch has been identified at time of analysis.

Authentication bypass in the RDK-B WebUI (broadband gateway management interface), build rdkb-2025q4-kirkstone.04.10.26, lets a remote unauthenticated attacker gain full administrative access by presenting a forged JWT whose RSA signature is invalid. The flaw lives in the signature-verification logic of jst_functions.c, which accepts tokens without properly validating the RSA signature. No public exploit is identified at time of analysis and EPSS is low (0.19%), but the CVSS 9.8 rating and trivial exploitation path make it a high-priority patch for exposed devices.

Unsigned x-amz-* header injection in Ceph Object Gateway (RGW) SigV4 allows any holder of a presigned URL to attach arbitrary unsigned x-amz-* headers - such as ACL grants, copy-source directives, or storage-class overrides - that RGW silently honors without verifying they were covered by the original cryptographic signature. Affected versions are Ceph prior to 19.2.6 and prior to 20.2.4; the flaw directly enables privilege escalation beyond the permissions the URL signer intended. No public exploit code or active exploitation is confirmed at time of analysis, and vendor-released patches for both stable branches are available.

Multiple cryptographic implementation defects in the libcrux Rust crates - libcrux-ecdh, libcrux-ed25519, and libcrux-psq - expose applications to availability failures and potential key-material weaknesses. libcrux-ecdh omitted length validation and clamping enforcement on X25519 secret inputs (including a broken clamping check for imported keys), libcrux-ed25519 applied a duplicated clamping step during key generation that could silently corrupt key material, and libcrux-psq panicked on AEAD decryption errors instead of returning them to callers. Vendor-released patch versions 0.0.6 (ecdh, ed25519) and 0.0.7 (psq) resolve all three defects; no public exploit code or CISA KEV listing has been identified at time of analysis.

FreeBSD's wg(4) WireGuard kernel driver silently accepts packets bearing invalid Poly1305 authentication tags, completely defeating WireGuard's cryptographic integrity guarantee on affected FreeBSD versions. The driver dispatches decrypt operations to the OpenCrypto Framework (OCF) but never checks the returned MAC verification result, meaning tampered or forged ciphertext passes through as legitimate plaintext. Two distinct attack paths exist: an on-path attacker who can intercept WireGuard UDP traffic can modify ciphertext and authenticated data without detection, while a remote attacker with knowledge of the receiver's replay window bounds can inject forged transport data packets directly. No public exploit has been identified and EPSS sits at 0.18% (8th percentile), indicating no widespread automated exploitation at time of analysis.

Signature-verification bypass in the Net::OAuth Perl module before 0.33 lets a remote attacker forge valid OAuth requests for any consumer key and token by dictating which algorithm the Service Provider uses to check their signature. Because verify() resolves the signature-method class from the attacker-supplied signature_method parameter and offers no way to pin an expected method, a provider deployed on RSA-SHA1 (which holds only the consumer's public key) can be tricked into validating an HMAC-SHA1 signature against a placeholder/guessable consumer_secret. No public exploit has been identified at time of analysis and EPSS is low (0.11%), but the flaw is unauthenticated and network-reachable (CVSS 9.8).

Secure boot bypass in the Ingenic T31 SoC allows an attacker with physical write access to boot media to forge SPL (Secondary Program Loader) images that pass RSA signature verification without the OEM signing key. The boot ROM's flash-boot verification path compares only a single 32-bit word of the RSA signature output against a single 32-bit word of the SHA-256 payload digest - rather than validating the full cryptographic outputs - yielding a forgery success rate of approximately 2/3 per attempt. End-to-end hardware acceptance of a forged firmware image on a Wyze Video Doorbell v2 (T31X) has been confirmed by external researchers at opensensor.io; no public exploit is confirmed in CISA KEV, but a working proof-of-concept exists per the researcher disclosure.

JWT signature validation is entirely absent in Otalio Ship Property Management System before version 2.22.0, allowing any authenticated user to forge arbitrary token claims and escalate to higher privilege levels. Because the server accepts tampered JWT payloads without verifying the cryptographic signature, a low-privileged account holder can self-promote to administrator or other elevated roles by modifying their own token. Mandiant disclosed this flaw; no public exploit code or CISA KEV listing has been identified at time of analysis.

Authentication bypass in the openssl_encrypt Python library (versions before 1.4.0) lets attackers who can tamper with ciphertext in transit defeat integrity protection, because a failed AES-GCM authenticated decryption in pqc.py silently falls back to unauthenticated AES-CTR. Reported by VulnCheck and carrying a CVSS 4.0 base score of 9.3, the flaw enables undetected bit-flipping and ciphertext manipulation. No public exploit identified at time of analysis, but a vendor patch is available.

Secret disclosure affects the openssl_encrypt Python library (all versions before 1.4.0), where PublicKeyBundle.from_dict() constructs key bundles from untrusted serialized data without validating the embedded self-signature, and to_identity() then promotes that unverified bundle into a usable Identity. An application that deserializes an attacker-supplied bundle and encrypts to it - without an intervening verify_signature() call - will encrypt secrets to an attacker-controlled public key, allowing the attacker to decrypt them. Reported by VulnCheck and fixed in 1.4.0; no public exploit has been identified at time of analysis.

Key-based authorization bypass in @fastify/jwt before 10.2.2 permits any low-privileged authenticated user holding a token signed by the application's global secret to access routes explicitly restricted to a separate per-request key, silently crossing a cryptographic trust boundary. Applications implementing multi-domain JWT authorization - for example, separating user and admin token verification keys - are specifically at risk, as the plugin's option merge incorrectly applies the global key last, overriding the developer-supplied per-request key. No public exploit code has been identified and the vulnerability is not listed in the CISA KEV catalog, but the fix is available in version 10.2.2 and the attack path is mechanically straightforward for any authenticated user.

Red Hat Quay's Stripe billing webhook handler at /webhooks/stripe processes inbound JSON payloads without verifying the Stripe-Signature HMAC header, enabling any network-reachable unauthenticated attacker to forge billing events. Successful exploitation resets the targeted namespace's build quota to its configured maximum and dispatches unsolicited billing notification emails to namespace administrators. No public exploit has been identified and EPSS is 0.14% (4th percentile), but the zero-prerequisite attack path makes exploitation trivially scriptable by any attacker with HTTP access to the endpoint.

Signature verification bypass in the PAX Technology Q80 payment terminal's application installer enables network-adjacent unauthenticated attackers to install unsigned or malicious applications, which when chained with a secondary vulnerability results in arbitrary code execution at the root privilege level. The flaw stems from the installer's failure to properly validate cryptographic signatures - tagged as a JWT attack vector - before accepting and executing application packages. No public exploit or confirmed active exploitation (CISA KEV) has been identified at time of analysis, though the formal ZDI advisory ZDI-26-526 publicly discloses the vulnerability details.

Supply chain compromise of Go module environments is possible when a malicious GOPROXY serves specifically crafted forged sumdb tile pairs, exploiting CWE-347 (improper cryptographic verification) in the cmd/go toolchain's tile-parent validation logic. Affected are cmd/go versions before 1.25.13, 1.26.6, and 1.27.0-rc.3 - any developer workstation or CI/CD pipeline using these versions and a non-default GOPROXY is at risk of silently caching attacker-controlled module content that cannot be distinguished from legitimate modules through normal transparency log evaluation. No public exploit has been identified and no CISA KEV listing exists; EPSS of 0.12% (3rd percentile) indicates low current exploitation probability, but the theoretical supply chain impact is severe.

Improper transparency log verification in the Go module checksum database (GOSUMDB) client allows a coordinating malicious GOPROXY and GOSUMDB pair to serve arbitrary, tampered module content to developers without triggering any client-side integrity error. All cmd/go versions before 1.25.13, 1.26.6, and 1.27.0-rc.3, as well as golang.org/x/mod/sumdb before 0.40.0, are affected. No public exploit code has been identified at time of analysis and CISA has not listed this in KEV, but the supply chain attack surface means developers may have silently pulled poisoned dependencies before patching, making retrospective verification via re-fetching module sums mandatory.

Authentication bypass in the miniOrange Headless Single Sign On WordPress plugin (versions 1.6 and earlier) allows unauthenticated remote attackers to forge or manipulate JWTs and assume the identity of any user, including administrators. The CWE-347 root cause (improper verification of a cryptographic signature) combined with a network attack vector yields a critical 9.8 CVSS. No public exploit identified at time of analysis, and it is not listed in CISA KEV.

Authentication bypass in ManageEngine Password Manager Pro (all versions before 13232) and PAM360 (all versions before 8551) allows low-privileged network attackers to forge SAML assertions and gain unauthorized elevated access, including administrative sessions, within these enterprise credential vaults. The flaw stems from improper cryptographic signature verification of SAML responses (CWE-347), enabling token manipulation that the service provider cannot detect. Vendor patch is available; no public exploit code has been confirmed at time of analysis, but the crown-jewel nature of PAM platforms - storing all privileged enterprise credentials - makes this a high-priority remediation regardless of current exploitation status.

JFrog Artifactory's JWT handling allows a holder of a valid integration credential to impersonate arbitrary users under specific conditions, exploiting an improper cryptographic signature verification flaw (CWE-347). Any actor in possession of a legitimate integration token - such as a CI/CD service account - can craft or manipulate JWT tokens to assume the identity of other users, including privileged ones, gaining their full access to repositories and administrative functions. No public exploit has been identified at time of analysis, and the vulnerability has not been added to the CISA KEV catalog; however, the full C:H/I:H/A:H CVSS impact profile warrants prompt patching in environments where integration credentials are broadly distributed.

SAML response impersonation in JFrog Artifactory (all tracked versions per CPE) permits an attacker who possesses a valid SAML response to assume the identity of another user under specific conditions. Rooted in CWE-347 (Improper Verification of Cryptographic Signature), the flaw indicates Artifactory fails to adequately validate SAML assertion signatures or cryptographic bindings - a class of weakness commonly exploited via XML Signature Wrapping (XSW) or assertion replay attacks. The 'JWT Attack' tag suggests Artifactory may internally convert SAML assertions to JWT tokens, and the signature verification gap may exist at that translation layer. No public exploit code and no CISA KEV listing have been identified at time of analysis.

Boot-stage integrity bypass in CPSD CryptoPro Secure Disk for BitLocker before v7.7.4 allows an attacker who can present a LUKS-encrypted volume during the pre-boot phase to cause bootxsa.efi to skip all CryptoPro file integrity checks, enabling execution of tampered EFI boot components. Publicly disclosed at Black Hat USA 2026 with an accompanying whitepaper, substantially raising the bar for exploit development. No CISA KEV listing and EPSS at the 1st percentile indicate no observed mass exploitation, but the research-quality disclosure significantly reduces attacker effort for targeted campaigns against affected endpoints.

Integrity-check bypass in CPSD CryptoPro Secure Disk for Bitlocker before v7.7.4 lets an attacker defeat the product's file-integrity verification: when a LUKS-encrypted volume is present, the software fails to validate that encryption correctly and then silently skips ALL CryptoPro integrity checks, so tampered files pass as trusted. This undermines the pre-boot/endpoint trust guarantees the product exists to provide, enabling evil-maid-style tampering. There is no public exploit identified at time of analysis, though the flaw is the subject of a Black Hat USA 2026 disclosure ('The Cost of Obscurity'); EPSS is very low (0.11%, 1st percentile) and it is not on CISA KEV.

Authentication bypass in Windows Schannel allows a network-based attacker to circumvent cryptographic signature validation, achieving high-integrity impact without requiring prior privileges. Schannel, Microsoft's TLS/SSL security provider, fails to properly verify cryptographic signatures - tagged as a JWT attack vector - enabling forged or malformed tokens to pass validation and bypass security feature enforcement. No active exploitation is confirmed (SSVC: exploitation=none; not listed in CISA KEV), and the high attack complexity and required user interaction constrain opportunistic mass exploitation despite the broad Windows version footprint.

SAML authentication bypass in PicketLink's Service Provider signature validation allows a network-accessible attacker with low privileges to forge a SAML response and authenticate as any principal with any role on the protected application. The flaw, rooted in CWE-347 (Improper Verification of Cryptographic Signature), arises because the signature check vacuously passes when the SAML response contains zero matching assertion elements, giving the attacker full control over identity and role claims presented to the SP. No public exploit code or CISA KEV listing has been identified at time of analysis, but the low attack complexity and high impact on confidentiality and integrity make this a critical authentication control failure.

Authentication bypass in Red Hat PicketLink Federation's SAML implementation lets unauthenticated remote attackers impersonate any principal in any role, because the unsolicited (IdP-initiated) response handler accepts forged SAML assertions without verifying their signature or validating their contents. Successful exploitation yields full identity spoofing, enabling information disclosure and access to restricted operations. No public exploit has been identified at time of analysis, but the CVSS 9.8 rating and trivial-to-forge nature make this a high-priority flaw for any application relying on PicketLink SAML SSO.

Session integrity bypass in SAP Approuter (node.js package versions prior to 23.0.0) enables an authenticated low-privilege attacker to hijack another user's session by sending crafted requests that circumvent header integrity verification on certain code paths. Exploitation demands prior out-of-band observation of the target's session values, constraining this to determined, targeted attackers rather than opportunistic mass exploitation. No public exploit code and no CISA KEV listing identified at time of analysis, but successful exploitation yields full read access to the victim's session context with a high confidentiality impact per CVSS.

Cryptographic signature validation failure in Pega Platform (Pega Infinity) versions 8.5.0 through 25.1.2 enables low-privileged network attackers to forge or manipulate JWT tokens, bypassing authentication and authorization controls. The vulnerability maps to CWE-347 and is tagged as a JWT attack vector capable of authentication bypass, with high confidentiality and integrity impact confirmed in the vendor's own CVSS 4.0 assessment. No public exploit code or CISA KEV listing has been identified at time of analysis, but the low attack complexity and network accessibility make this a meaningful risk for any organization running affected Pega Infinity deployments.

Improper cryptographic signature verification in Estonian RIA's libdigidocpp core library and its consumer applications - DigiDoc4, DigiDoc for Android, and DigiDoc for iOS - enables bypassing of XAdES signature validity checks through unhandled exceptional conditions during BDOC container parsing. Affected versions span libdigidocpp 4.1.0-4.2.0, DigiDoc4 4.7.0-4.8.1, DigiDoc Android 2.7.0-2.7.1, and DigiDoc iOS 2.8.0, all of which have vendor-released patches. A proof-of-concept is indicated by the CVSS 4.0 E:P exploit maturity modifier, though no active exploitation has been confirmed and this CVE is not listed in CISA KEV.

Cryptographic signature spoofing in Microsoft Teams exposes enterprise collaboration environments to unauthenticated identity impersonation over the network. The flaw, tagged as a JWT attack enabling authentication bypass, allows a remote attacker with no prior credentials to forge or tamper with token-based identity claims that Teams fails to properly verify. No active exploitation has been confirmed by CISA KEV, and no public proof-of-concept has been identified at time of analysis, though the CVSS vector (AV:N/AC:L/PR:N/UI:N) indicates a low-barrier, remotely exploitable path with high integrity impact.

Privilege elevation in Microsoft 365 Admin Center allows a remote, unauthenticated attacker to gain elevated permissions by exploiting improper verification of a cryptographic signature (CWE-347), consistent with the vendor-supplied 'Authentication Bypass' and 'JWT Attack' tags. The maximal 9.8 CVSS with a fully network-reachable, no-privilege, no-interaction vector makes this a critical bypass of the admin portal's trust boundary. No public exploit identified at time of analysis, and it is not currently listed in CISA KEV.

Authentication bypass in WSO2 API Manager and related components (Universal Gateway, Traffic Manager, API Control Plane, and the Carbon API Manager REST API Utility) allows remote unauthenticated attackers to forge JWT tokens because the authentication layer accepts tokens signed with algorithms outside the explicitly configured/supported set. By crafting a JWT with an unsupported or attacker-chosen algorithm that is then incorrectly validated, an attacker can gain unauthorized access up to full administrative account takeover. Rated CVSS 10.0 (scope-changed) by WSO2, with the description noting a contained 9.8 score for single-tenant deployments; no public exploit identified at time of analysis.

Authentication bypass in Progress MarkLogic Server (versions before 11.3.6 and 12.0.3) lets an unauthenticated remote attacker forge SAML assertions and impersonate any user, including administrators, on deployments where SAML single sign-on is enabled. The flaw stems from improper cryptographic signature verification (CWE-347) in the SAML authentication module, yielding full identity spoofing over the network with low complexity and no user interaction. No public exploit identified at time of analysis, and the CVE is not listed in CISA KEV, but the 9.1 CVSS and pre-authentication admin impersonation make it a high-priority patch.

Authentication bypass in Red Hat Build of Keycloak (and Red Hat Single Sign-On 7) lets an unauthenticated attacker forge SAML responses to hijack accounts when a SAML identity-provider's metadata was imported without explicit key-usage attributes, causing the keycloak-services identity-brokering engine to silently disable signature validation despite a signing certificate being present. Rated CVSS 9.1 with total technical impact per CISA SSVC, an attacker who knows a victim's external identifier can log in as that user. No public exploit identified at time of analysis, and EPSS is low (0.14%, 4th percentile), indicating the risk is currently theoretical/targeted rather than mass-exploited.

Forced logout via unsigned backchannel requests affects Red Hat Build of Keycloak when an OIDC identity provider is configured to skip signature validation. Under this non-default configuration, the backchannel logout endpoint in keycloak-services improperly accepts logout requests lacking any cryptographic signature (CWE-347), violating the OIDC backchannel logout specification. An unauthenticated network attacker who possesses knowledge of a target user's session identifiers can submit a forged unsigned logout request, terminating that session without the user's consent. No public exploit or active exploitation (CISA KEV) has been identified; with CVSS 3.7 and EPSS data absent from the input, this is a low-priority availability-only issue gated by a specific non-default configuration.

Signature validation bypass in Misskey (versions 12.37.0 through prior to 2026.5.4) allows an attacker to have spoofed ActivityPub activities accepted as authentic. The flaw resides in the JSON-LD signature validation and compaction logic (CWE-347), enabling forgery of federated actions such as posts or actions attributed to other actors/instances. The CVSS 4.0 base score is 9.2 (Critical) with a network, unauthenticated, low-complexity vector emphasizing integrity impact; no public exploit has been identified at time of analysis, and it is not listed in CISA KEV.

Signature verification bypass in XML::Sig (Perl) versions 0.29 through 0.71 allows remote unauthenticated attackers to submit arbitrary XML documents that are accepted as cryptographically valid without any digest or key check ever running. The verify() function unconditionally returns true after looping over all dsig:Signature elements, even when every iteration exited early via a skip path before cryptographic validation. No public exploit has been identified beyond the proof-of-concept test case embedded in the fix commit, and this vulnerability is not currently listed in the CISA KEV catalog.

XML Signature Wrapping in Net::SAML2 before 0.86 allows any party holding a single valid IdP-signed assertion to authenticate as an arbitrary user against Perl applications that use this SAML SP library. Identity fields - NameID, attributes, SessionIndex, audience - are extracted via document-wide XPath queries selecting the first matching element in document order, not the element covered by the verified signature; an attacker who prepends an unsigned forged assertion to a Response containing their own legitimate signed assertion bypasses identity verification entirely while the signature check still passes. A vendor-released patch exists in version 0.86, and no public exploit has been identified at time of analysis.

Signature verification bypass in the Perl XML::Sig module before 0.71 allows XML Signature Wrapping (XSW) via duplicate ID attributes, letting attackers forge signed content that still validates. verify() resolves a signed Reference URI with the XPath "//*[@ID='$id']" and trusts the first matching node, so a document containing two elements with the same ID passes verification while a downstream consumer reads the attacker-supplied second element; in a SAML2 SP this puts Assertion contents under attacker control. Rated CVSS 9.1 (network, no authentication, no user interaction); no public exploit identified at time of analysis, though the vendor's fix ships a regression test that reproduces the technique.

Authentication bypass in the Net::SAML2 Perl module before 0.86 lets an unauthenticated attacker log in as any user against Service Providers that accept EncryptedAssertions. The flaw stems from _verify_encrypted_assertion returning a decrypted assertion as 'verified' whenever it contains no dsig:Signature element, skipping both the signature and trust-anchor checks. Because an SP publishes its encryption certificate in SAML metadata, anyone can encrypt a forged unsigned assertion to it, wrap it in a samlp:Response, and post it to the assertion consumer service; no public exploit identified at time of analysis but the logic bug is trivially reproducible.

SAML authentication bypass in Net::SAML2 versions before 0.86 for Perl allows remote unauthenticated attackers to forge arbitrary SAML assertions against service providers that omit a trust anchor during library configuration. The flaw is in verify_xml, which exits early after validating the XML signature against the certificate embedded within the response itself - meaning an attacker who controls the response can supply their own self-signed certificate and sign any assertion they choose. No public exploit is identified at time of analysis, but the vulnerability is mechanically trivial to reproduce given that the vulnerable code path is fully documented in referenced MetaCPAN source files.

RSA PKCS#1 v1.5 signature forgery is possible in Bouncy Castle for Java (bc-java before 1.85, bc-lts-java before 2.73.12) when the DigestInfo encoding omits the NULL AlgorithmIdentifier parameter. The off-by-two bytes in the RSADigestSigner comparison loop allows any forged signature whose DigestInfo matches all bytes except the final two of the message hash to pass verification as valid, achieving a high-integrity bypass. No public exploit has been identified at time of analysis, but the public patch commit includes a step-by-step test demonstrating the exact forgery technique, substantially lowering the bar to exploitation.

Signature bypass in Bouncy Castle for Java allows any attacker-supplied content wrapped in a zero-signer CMS envelope to pass `CMSSignedData.verifySignatures()` without any valid cryptographic signature. The method iterates an empty signerInfos SET, falls through to a vacuous `return true`, and any application using it as its top-level authenticity check silently accepts unsigned attacker-controlled content as authenticated - a classic fail-open flaw (CWE-347). No public exploit has been identified at time of analysis and the vulnerability is not listed in CISA KEV, but the attack primitive is trivially constructible using any standard CMS/PKCS#7 library.

OpenPGP inline-signature policy enforcement in Bouncy Castle for Java silently discards rejection exceptions, causing signatures that use prohibited weak hash algorithms (MD5, SHA-1, RIPEMD-160) or otherwise violate the configured OpenPGPPolicy to be reported as cryptographically valid. Affected are bc-java before 1.85 and bcpg-fips (bc-fja) before 2.0.13; the detached-signature and prefixed-signature verification paths are not affected - only the inline one-pass path. A vendor patch is available; no public exploit code has been identified at time of analysis, though the CVSS 4.0 score of 8.7 reflects a high integrity impact driven by the unauthenticated network vector.

Session revocation denial-of-service in ueberauth Guardian (Elixir) allows an unauthenticated network attacker to forcibly terminate any user's active session by submitting a cryptographically forged JWT to a logout endpoint. Guardian.revoke/3 extracted claims via peek/1 - which only base64-decodes the JWT without verifying the signature - and passed those unverified claims directly to the token store's revocation callback, enabling a forged token carrying a victim's jti or sub values to evict a legitimate session. The vulnerability spans all production releases 1.0.0 through pre-2.4.1; no public exploit or CISA KEV listing exists at time of analysis, but the attack requires only knowledge of a victim's identifying JWT claims.

Session revocation via forged cookies in better-auth's multi-session plugin (npm, versions 1.3.34 through <1.4.0) allows any authenticated attacker to arbitrarily delete session tokens belonging to other users by supplying a crafted `_multi-*` cookie to the /sign-out after-hook, which forwards cookie values to `internalAdapter.deleteSessions()` without verifying the cryptographic signature. The flaw is not listed in the CISA KEV catalog and no public exploit code has been identified, but the low attack complexity makes unauthorized targeted session termination straightforward once an attacker holds any valid application session. Version 1.4.0 resolves the issue via patch commit cfc453a2a6eb02951f9a0a7c944064936e73eee8.

HMAC-SHA1 URL signature bypass in Thumbor (pip/thumbor ≤ 7.7.7) allows unauthenticated remote attackers to defeat the signed URL security mechanism by injecting duplicate signature strings into the request path. Python's global `str.replace()` removes all occurrences of the signature during pre-validation stripping, causing the validated URL to differ from the actual requested resource. No public exploit code is identified at time of analysis, though the detailed disclosure and fix commit make independent exploitation straightforward; this is not listed in CISA KEV.

Unauthenticated firmware implantation in Phoenix Contact CHARX SEC-3000/3050/3100/3150 EV charging controllers allows a remote attacker to push a modified firmware image to the basemodule because the update routine only checks a CRC32 checksum and performs no cryptographic signature verification (CWE-347). A successful upload yields full system compromise of the controller. No public exploit has been identified at time of analysis, but the flaw is network-reachable with no authentication and a vendor patch (v1.9.1) is available.

Sandbox escape in Google Chrome on Android (versions prior to 151.0.7922.72) stems from a cryptographic flaw in the WebAppInstalls component, exploitable by a local attacker via a crafted HTML page. The CVSS scope change (S:C) confirms the exploit crosses Chrome's sandbox security boundary, enabling impact on resources outside the browser process. No public exploit code and no CISA KEV listing have been identified at time of analysis; EPSS is extremely low at 0.12% (2nd percentile), indicating minimal observed exploitation pressure.

Arbitrary code execution in Autel MaxiCharger AC Elite Home EV chargers is possible for physically present attackers who supply a crafted, unsigned or improperly signed firmware update image to the device. The flaw (CWE-347) stems from the absence of cryptographic signature validation during the software update process - tagged as a JWT attack vector - meaning the update mechanism accepts attacker-controlled images without verifying their authenticity. No public exploit has been identified at time of analysis, and exploitation requires physical proximity, but a successful attack achieves full code execution in the device context with high confidentiality, integrity, and availability impact.

Two-factor authentication bypass in Koollab LMS allows attackers to supply a client-controlled TOTP seed and generate a valid one-time password, bypassing the second authentication factor. This can lead to unauthorized access to administrator accounts if TOTP is enabled. No public exploit or active exploitation has been identified at time of analysis.

Authentication bypass in Apache Airflow FAB provider allows unauthenticated attackers to log in as any user (including Admin) by sending a forged Azure AD ID token to the OAuth callback endpoint. This affects default deployments of the FAB auth manager with Azure AD OAuth login enabled, prior to version 3.7.3. The vulnerability stems from `verify_signature` defaulting to `False`, enabling acceptance of unsigned or algorithm-none tokens.

Privilege escalation in JFrog Artifactory allows low-privileged authenticated users to forge administrator JWTs by exploiting missing signature validation on refresh tokens. An attacker with any user account can gain full admin control, rated CVSS 8.8. No active exploitation or public exploit is confirmed at this time.

Privilege escalation in Lenze C430, C520, C550, and i950 series devices allows low-privileged local attackers to bypass SSH enablement signature verification. This enables unauthorized SSH access, leading to complete system compromise. The vulnerability is tracked under CVE-2026-14837 and was reported by CERTVDE; no public exploit or active exploitation (KEV) has been confirmed at this time.

DNSSEC validation is bypassed in PowerDNS Recursor when wildcard-synthesized answers are CNAME or DNAME record types, allowing an attacker positioned to inject forged DNS responses to circumvent cryptographic integrity guarantees. Wildcard expansion proofs - the NSEC or NSEC3 records that DNSSEC uses to prove a wildcard match is legitimate - are accepted by the recursor without verifying their signatures in this specific code path. No public exploit code has been identified at time of analysis, and EPSS data was not provided; however, the bypass of DNSSEC undermines a core trust mechanism used by resolvers to reject forged DNS data.

ID Token signature verification bypass in OIDC::Lite Perl library through version 0.12.1 allows unauthenticated remote attackers to forge authentication tokens by controlling the algorithm allowlist used during verification. When a relying party calls the verify method without pinning a specific algorithm, the library extracts the ‘alg’ value from the attacker-controlled token header and passes it as an accepted-algorithm allowlist, enabling ‘alg=none’ (no signature check) or key‑confusion attacks (e.g., RS256 to HS256). An attacker can impersonate any user by crafting a token with arbitrary ‘sub’ claims. No active exploitation has been confirmed, and the EPSS score (0.17%) suggests low immediate threat, but the issue is critical for unpatched systems using the unpinned verification path.

DNSSEC integrity bypass in ISC BIND 9 enables network-positioned attackers to forge authenticated NXDOMAIN responses by exploiting improper validation of NSEC3 records originating from child zones. Affected are BIND 9 versions across the 9.18, 9.20, and 9.21 branches, as well as the BIND 9 Supported Preview Edition (S-series). Because the CVSS vector carries S:C (scope changed), the integrity impact propagates beyond the resolver itself to any DNS client trusting BIND's DNSSEC-validated answers. No public exploit code has been identified and the vulnerability is not listed in the CISA KEV catalog at time of analysis.

Signature-verification bypass in Network-AI before 5.13.4 lets unauthenticated remote attackers forge APS delegation payloads and mint signed permission-grant tokens for privileged scopes, including SHELL_EXEC. The root cause is a default local verifier in APSAdapter that treats any non-empty string as a valid cryptographic signature, so no real key material or authentication is needed. No public exploit identified at time of analysis, and the flaw is not listed in CISA KEV, but the trivial exploitation logic and network reachability make it a high-priority fix.

Signature bypass in Janssen jans-auth-server's OIDC authorization request object processing allows unauthenticated remote attackers to submit JWE-wrapped authorization requests containing unsigned plain JSON payloads, circumventing the integrity guarantee that JAR (RFC 9101) is designed to enforce. Two distinct code defects enable the bypass: the server silently skips nested JWS validation when getSignedJWTPayload() returns null, and the forceSignedRequestObject enforcement fails to reject null-mapped algorithm identifiers such as RSA-OAEP (an encryption algorithm, not a signature algorithm). No public exploit code has been identified and the vulnerability is not listed in CISA KEV; it is fixed in version 2.0.0.

Authentication bypass in the Microsoft 365 / Microsoft Entra ID (local_o365) plugin for Moodle allows an unauthenticated attacker to forge a JWT and log in as any Office 365-linked Moodle user before versions 4.5.6, 5.0.5, and 5.1.1. The Teams SSO endpoint sso_login.php base64-decodes the JWT payload and trusts the 'upn' claim without verifying the token signature, so a self-signed or hand-crafted token is accepted as valid. There is no public exploit identified at time of analysis and it is not in CISA KEV, but the flaw is trivially exploitable and confirmed by a Microsoft GitHub security advisory (GHSA-hqjh-93qv-47v5).

Authentication bypass in the miniOrange SAML Single Sign On - SSO Login plugin for WordPress (all versions through 5.4.3) lets unauthenticated attackers forge SAML assertions and seize any account, including administrator. The plugin trusts the SignatureMethod algorithm declared inside the attacker-supplied SAMLResponse, enabling an RSA-to-HMAC signature confusion attack that yields valid WordPress auth cookies and full admin takeover. Reported by Wordfence; no public exploit identified at time of analysis, but the flaw is trivially exploitable and carries a 9.8 CVSS.

Authentication bypass via forged JWTs in DataEase, an open-source data visualization and BI tool, allows remote unauthenticated attackers to impersonate any user (including administrators) in enterprise deployments before version 2.10.23. The enterprise TokenFilter passes attacker-supplied X-DE-TOKEN values to a validator that checks only token presence and length, then decodes the JWT without verifying its signature, so tokens with a chosen uid and oid are accepted whenever the enterprise license is valid (licenseValid=true). CVSS 4.0 rates this 9.5 (Critical); there is no public exploit identified at time of analysis and it is not listed in CISA KEV.

Security feature bypass in Microsoft .NET (shipped via Visual Studio 2022 17.12/17.14 and Visual Studio 2026 18.7) lets a remote, unauthenticated attacker defeat a cryptographic-signature check over the network — most likely a JWT/token signature verification flaw per the vendor 'Jwt Attack' and 'Authentication Bypass' tags. By forging or tampering with signed data the runtime fails to validate correctly, an attacker can impersonate trusted principals and undermine an authentication or integrity control. Microsoft has released a patch; there is no public exploit identified at time of analysis and it is not listed in CISA KEV.

Authentication bypass in Siemens Opcenter X (all versions before V2604) lets an unauthenticated remote attacker forge JSON Web Tokens by exploiting improper validation of the algorithm field in the JWT header. Because the application trusts the attacker-controlled 'alg' value, an attacker can craft tokens that impersonate any user - including administrators - yielding full unauthorized access to the manufacturing operations platform. Rated CVSS 10.0 with a scope-changing critical impact; no public exploit identified at time of analysis and it is not currently in CISA KEV.

Arbitrary code execution in the EVBEE DC-80 EV charging station stems from a firmware update mechanism that ships without cryptographic signature validation (CWE-347), letting an attacker who reaches the update capability push a malicious firmware image and have it executed by the device. Reported by DIVD (advisory DIVD-2026-00001) with a CVSS 4.0 base score of 9.3 and a 'Jwt Attack' angle noted in triage tags, the flaw grants full compromise of the charger. There is no public exploit identified at time of analysis and it is not listed in CISA KEV.

Signature-verification bypass in YesWiki (v4.6.5 and earlier, ActivityPub-federated Bazar forms) lets an unauthenticated remote attacker forge a valid ActivityPub actor and have Create/Update/Delete activities processed as if properly signed. The flaw stems from HttpSignatureService::verifySignature() using a loose boolean check (!openssl_verify(...)) that treats openssl_verify()'s -1 internal-error return as success. A detailed proof-of-concept exists (publicly available exploit code exists) demonstrating full CRUD on Bazar entries; the issue is not in CISA KEV and no EPSS score was provided.

Payment bypass in the CorvusPay WooCommerce Payment Gateway plugin (all versions up to and including 2.7.4) enables unauthenticated remote attackers to fraudulently mark any pending WooCommerce order as fully paid, obtaining goods or services without actual payment. The `corvuspay_success_handler` function registers a publicly accessible REST endpoint where a cryptographic signature validation is performed but its boolean result is silently discarded - written only to a debug log - causing `$order->payment_complete()` to execute unconditionally regardless of signature validity. WooCommerce order IDs are sequential integers, making every pending order on an affected store trivially enumerable with no prior knowledge required. No public exploit code or CISA KEV listing was identified at time of analysis.

Signature verification bypass in HAVELSAN Liman MYS (versions before release.Master.1107) lets remote attackers forge the source/authenticity of data - tagged as a JWT attack - enabling identity spoofing and likely authentication bypass. Per CVSS the vector is network-based and unauthenticated (AV:N/PR:N) with high impact to confidentiality and integrity. No public exploit is identified at time of analysis and it is not on CISA KEV.

Cross-repository information disclosure and cross-task tampering in Gitea's self-hosted Git server (fixed in v1.26.2) arises from an HMAC signature ambiguity in the Actions Artifacts V4 signed-URL scheme, letting an authenticated low-privilege user reuse a validly signed URL outside its intended repository or task context. An attacker with access to a single Actions task can read private artifacts belonging to other repositories and write upload-state for tasks they do not own, crossing the repository trust boundary (CVSS 9.6, scope-changed). There is no public exploit identified at time of analysis, and it is not listed in CISA KEV.

Firmware signature validation bypass in WatchGuard Fireware OS lets an authenticated administrator upload a tampered firmware image through the backup/restore feature and have it installed despite failing integrity checks. Affecting Fireware OS branches 11.0 through 11.12.4_Update1, 12.0 through 12.12, and 2025.1 through 2025.6.2, the flaw (CWE-347) enables persistent malicious code on the appliance. No public exploit identified at time of analysis and it is not listed in CISA KEV, but the high integrity/confidentiality/availability impact and the appliance's privileged network position make it significant.

Signature forgery and denial-of-service in Libreswan's IKEv1 RSA authentication allows a remote unauthenticated attacker to impersonate an IKE peer or crash the daemon. The flaw lives in RSA_authenticate_hash_signature_raw_rsa(), which fails to validate the length of the authentication hash inside a PKCS #1 (RFC 2313) encoded SIG payload; when a peer uses a small RSA public exponent such as e=3, a Bleichenbacher-style forgery becomes feasible. There is no public exploit identified at time of analysis and it is not in CISA KEV, but the impersonation impact against IKEv1 raw-RSA authentication makes this a high-severity issue (CVSS 8.1); remote code execution is explicitly not possible and X.509 certificate verification is unaffected.

Peer impersonation and denial-of-service in Libreswan IPsec/IKEv2 arises from improper DER/ASN.1 digest verification in RSA_authenticate_hash_signature_pkcs1_1_5_rsa() when the IKEv2 AUTH payload uses RSASSA-PKCS1-v1_5 signatures. A remote unauthenticated attacker can mount a Bleichenbacher-style forgery to impersonate a peer when small RSA public exponents (e.g., e=3) are in use, or send an undersized hash to trip an assertion that aborts and restarts the daemon for sustained DoS. A vendor patch is available and there is no public exploit identified at time of analysis; RCE is not possible and X.509 certificate verification of the peer is unaffected.

Improper cryptographic signature verification in the CubeSpace CW0057 Reaction Wheel firmware (versions prior to 5.0.20) permits an attacker with physical access to flash arbitrary, unsigned firmware onto the device without any authentication. This affects a safety-critical spacecraft attitude control component used in CubeSat and small satellite missions, where unauthorized firmware replacement could cause mission-critical failures including attitude loss or uncontrolled spacecraft behavior. A proof-of-concept exploit exists (indicated by E:P in the CVSS 4.0 supplemental vector); no active exploitation has been confirmed by CISA KEV at time of analysis.

Cross-tenant JWT authentication bypass in Centrifugo (v3 through v6) lets an attacker holding a valid token for one allowed issuer/tenant authenticate as a different issuer/tenant when the server uses dynamic JWKS endpoint templates. The flaw stems from the JWKS cache and singleflight lookup being keyed only by the JWT header 'kid', so a key fetched for tenant A is reused to verify a token claiming tenant B whenever both JWKS documents share the same 'kid' and tenant A's key is cached first. Publicly available exploit code exists in the form of a reporter-supplied Go unit-test PoC; there is no evidence of active exploitation, and the CVSS base score is 8.2 (AC:H, PR:L, scope-changed).

Signature verification policy bypass in the sigstore npm package allows attackers to have unauthorized signing certificates accepted despite explicit OID-based restrictions. The documented `certificateOIDs` verify option - used by `sigstore.verify()` and `createVerifier()` to require specific Fulcio/workload-identity extension OIDs - is silently discarded during policy construction, so those extension constraints are never enforced while callers believe they are. Publicly available exploit code exists (a proof-of-concept in the advisory), but there is no evidence of active exploitation; EPSS/KEV not indicated in the source data.

Certificate timestamp validation bypass in sigstore-java 2.0.0 allows an attacker who has already exfiltrated an ephemeral Sigstore signing key to reuse an expired Fulcio certificate, causing bundle verification to succeed when it should fail. PR #1008 erroneously removed the check that bounds a Rekor V1 log entry's `integratedTime` against the Fulcio certificate's validity window, a regression only present in the 2.0.0 release and fixed in 2.1.0. No public exploit identified at time of analysis beyond the vendor-provided proof-of-concept test bundle in sigstore-conformance; CVSS base score of 2.0 reflects the extremely narrow, high-privilege, local-only attack conditions required.

Firmware update signature bypass in Hitachi Virtual Storage Platform One Block models 23, 24, 26, and 28 allows an authenticated remote attacker to supply unvalidated firmware packages, potentially compromising storage array integrity and availability. The root cause is CWE-347 (Improper Verification of Cryptographic Signature), and the 'Jwt Attack' tag suggests the firmware validation chain relies on a JWT-based signing mechanism that can be circumvented under specific conditions. No public exploit code exists and the vulnerability is not listed in CISA KEV, but the self-disclosure by Hitachi with a coordinated patch release indicates vendor-confirmed severity.

Signature type-binding bypass in @sigstore/core (npm) allows an attacker who controls the `payloadType` field of a DSSE envelope to substitute every ASCII character with a Unicode variant whose low byte matches, producing PAE bytes identical to a legitimate signature and causing verification to pass for a mismatched content type. All versions up to and including 3.2.0 are affected; a working proof-of-concept is included in the GitHub security advisory GHSA-jfc7-64v2-mr8c. The vulnerability is not confirmed in the CISA KEV catalog, but exploit code is publicly available, making exploitation straightforward for any attacker positioned to craft or relay DSSE envelopes.

JWT algorithm confusion in Netflix Lemur 1.9.0 allows an attacker to control which signing algorithm the server trusts by supplying an arbitrary alg value in the unverified token header, which is passed directly to pyjwt.decode() instead of a server-pinned allowlist. On current PyJWT 2.x deployments the standalone impact is limited to audit-log blinding and a durable algorithm-downgrade primitive; full account takeover requires chaining with a separate LEMUR_TOKEN_SECRET disclosure vulnerability, after which a forged HS256 admin JWT yields HTTP 200 with role=admin. A public proof-of-concept walkthrough exists (asciinema); no active exploitation is confirmed in CISA KEV.

Signer confusion in wolfSSL's PKCS7_verify implementation allows a crafted PKCS#7 message to report a trusted certificate as the signer even when an attacker-controlled certificate produced the actual signature. Any application using wolfSSL for PKCS#7 signature verification - including JWT workflows flagged in the CVE tags - may incorrectly authorize operations as if from a trusted party. No public exploit has been identified at time of analysis, but the upstream fix is available as GitHub PR #10203 and the vulnerability is straightforwardly reproducible by anyone familiar with PKCS#7 certificate bundle structure.