Red Hat Hardened Images

Out-of-bounds write in GNU binutils' BFD library (bfd/elf32-dlx.c) lets a crafted ELF/DLX object file corrupt memory and achieve arbitrary code execution when parsed by any BFD-consuming tool (objdump, readelf, strip, ld, nm, objcopy). Reported by Red Hat and tracked against RHEL 6-10, Hardened Images and OpenShift 4, the flaw is only reachable when binutils is compiled with the DLX backend (typically --enable-targets=all), so exposure is gated by a non-default build option. There is no public exploit identified at time of analysis (not in CISA KEV), though the researcher demonstrated code execution via a File Stream Oriented Programming (FSOP) attack on glibc FILE structures.

Out-of-bounds heap read in GNU Binutils linker when processing 32-bit XCOFF files allows local attackers to disclose heap memory and cause denial of service. Affects Red Hat Enterprise Linux 6 through 10, Hardened Images, and OpenShift Container Platform 4. No public exploit or active exploitation identified at time of analysis; EPSS data unavailable.

Denial of service in dbus-broker allows a local attacker to crash the user session bus broker when file descriptor limits are exhausted. Affected products include Red Hat Enterprise Linux 9/10, Red Hat OpenShift Container Platform 4, and Red Hat Hardened Images where dbus-broker is deployed. No active exploitation or public exploit code is known, and EPSS indicates low exploitation probability (0.11%).

Symlink-following vulnerability (CWE-59) in systemd-tmpfiles allows a local, low-privileged user to redirect privileged file write operations to an attacker-controlled path on affected Red Hat Enterprise Linux systems. The flaw resides in the path resolution logic within chase.c, where a safety check incorrectly treats all transitions away from the root user as inherently safe - failing to detect attacker-placed symlinks at tmpfiles.d target path components. Exploitation is constrained by high attack complexity requiring a specific non-default tmpfiles.d configuration, and no public exploit code or CISA KEV listing has been identified at time of analysis.

Privilege escalation via authentication bypass in libssh affects servers that enable GSSAPIKeyExchange, where the gssapi-keyex authentication path fails to confirm that the authenticated Kerberos principal is actually authorized for the local user account being requested. An already-authenticated client holding any valid Kerberos principal in the realm can therefore log in as an arbitrary user, including potentially privileged accounts, on Red Hat Enterprise Linux 8, 9, and 10 and Red Hat Hardened Images. No public exploit is identified at time of analysis and the issue is not listed in CISA KEV, but the CVSS of 8.8 reflects a straightforward, low-complexity abuse once a valid Kerberos credential is held.

Denial of service (and potential use-after-free) in libssh occurs when the library processes SSH data packets that arrive after a channel has been closed, causing channel data callbacks to fire against already-freed memory. Any application or system linking the affected libssh - including Red Hat Enterprise Linux 8, 9, and 10 and Red Hat Hardened Images - can be crashed by a malicious SSH peer that sends channel data at the wrong point in the connection lifecycle. There is no public exploit identified at time of analysis, EPSS is low (0.26%), and CISA SSVC scores exploitation as none, indicating a real but non-urgent memory-safety fix.

Denial of service in libssh affects clients that use automatic certificate-based public key authentication, where logic errors cause the client to loop indefinitely when configured certificates are absent or are repeatedly rejected by the SSH server. Reported by Red Hat and shipped in Red Hat Enterprise Linux 8, 9, and 10 plus Red Hat Hardened Images, the flaw lets a hostile or misconfigured server hang a connecting client and consume CPU. There is no public exploit identified at time of analysis, and EPSS is low at 0.17% (7th percentile), consistent with an availability-only, client-side bug rather than a mass-exploited issue.

Unbounded memory growth in libssh's SFTP client allows a malicious server to exhaust client-side memory by sending responses for unknown request IDs, resulting in a denial-of-service condition against any application using libssh for SFTP operations. Affected deployments include libssh as packaged in Red Hat Enterprise Linux 8, 9, 10, and Red Hat Hardened Images. No public exploit code and no active exploitation have been identified at time of analysis; the CVSS score of 5.3 (Medium) reflects the limited availability impact and the requirement that a victim client connect to an attacker-controlled server.

Integrity-protection bypass in libssh builds compiled against the OpenSSL crypto backend, caused by incorrect AES-GCM finalization checks that fail to verify the authentication tag. An in-path (man-in-the-middle) attacker positioned on an SSH session can silently alter plaintext bytes on the wire without triggering a MAC/integrity failure, defeating a core guarantee of the SSH transport layer. There is no public exploit identified at time of analysis, EPSS risk is low (0.28%, 20th percentile), and CISA SSVC rates exploitation as 'none' though 'automatable: yes'.

Memory exhaustion in libssh's SFTP server subsystem allows authenticated remote clients to degrade or crash the service by sending SSH_FXP_READ requests specifying an arbitrarily large read length, causing the server to allocate unbounded memory for each request. The CVSS vector (PR:L) confirms exploitation requires valid credentials, limiting the attack surface to authenticated SFTP users. No public exploit code and no CISA KEV listing have been identified at time of analysis, though the low complexity and network-accessible attack path make this a realistic insider or credential-abuse scenario.

Signal misdelivery in libssh's ProxyCommand handling allows a low-privileged local user to trigger a local denial of service affecting their entire accessible process tree. When fork() fails during ProxyCommand execution, the error return value of -1 is stored unchecked as a child process ID; at cleanup, libssh signals PID -1, which Linux interprets as a broadcast to all processes the caller has permission to signal. No public exploit code has been identified at time of analysis, and the vulnerability is not listed in CISA's KEV catalog, but the CVSS scope-changed metric (S:C) confirms that impact extends beyond the libssh component itself to co-located user processes.

CPU exhaustion via malformed SSH channel negotiation in libssh allows an authenticated remote peer to cause indefinite server-side looping and denial of service. By advertising a zero maximum packet size in SSH_MSG_CHANNEL_OPEN, the attacker forces subsequent channel writes into an infinite loop, fully consuming CPU on the affected host. This affects libssh as shipped in Red Hat Enterprise Linux 8, 9, and 10 and Red Hat Hardened Images; no public exploit or CISA KEV listing has been identified at time of analysis.

Out-of-bounds heap read in libssh exposes small amounts of server memory during GSSAPI key exchange, exploitable by remote unauthenticated attackers. When a client submits a Curve25519 public key shorter than the expected 32 bytes during server-side GSSAPI key exchange, libssh copies the key without validating its length, triggering a read beyond the intended buffer boundary. No public exploit has been identified at time of analysis; exploitation is constrained to servers with GSSAPI key exchange explicitly enabled, which is a non-default configuration.

Denial of service in libsolv's PGP signature verification (solv_pgpvrfy) allows remote attackers to crash automated package and repository processing by supplying a crafted Ed25519 signature. The flaw is a stack-based buffer overflow (CWE-121) triggered when the EdDSA 's' MPI is copied into a fixed 64-byte stack buffer using an attacker-controlled mismatched length. It affects the libsolv dependency solver embedded in Red Hat Enterprise Linux 7/8/9/10, OpenShift, Satellite, RHUI, openSUSE/SUSE, Ubuntu and Debian; no public exploit identified at time of analysis and it is not in CISA KEV.

Use-after-free in the SSSD PAM responder crashes the authentication daemon when a local attacker manipulates YubiKey or smartcard contents during an authentication attempt on Red Hat Enterprise Linux 6 through 10. The primary realized impact is a denial of service - the PAM responder crash disrupts all authentication - but the underlying memory corruption also presents a difficult-to-exploit privilege escalation path. No public exploit code exists at time of analysis, and the CVSS vector (AV:L/AC:H/PR:H) reflects a tightly constrained local attack requiring high privileges and significant complexity, limiting realistic blast radius to insider-threat and physical-access scenarios.

Denial of service in libarchive's RAR5 reader allows remote attackers to crash applications that decompress untrusted RAR5 archives via a double-free (CWE-415) of the stale filtered_buf pointer. Reported by Red Hat and affecting libarchive as shipped across Red Hat Enterprise Linux 6 through 10, OpenShift Container Platform 4, and Red Hat Hardened Images, the flaw is triggered purely by parsing a malicious archive entry. No public exploit has been identified and the issue is not in CISA KEV; impact is limited to availability (CVSS 7.5, A:H only) with no code execution or data exposure claimed.

Stack exhaustion in p11-kit's RPC server crashes the daemon and any dependent cryptographic services on affected Red Hat systems. The vulnerability exists in the PKCS#11 RPC message parsing layer, where two attribute-handling functions form a mutually-recursive call chain with no depth limit when processing nested CKA_WRAP_TEMPLATE, CKA_UNWRAP_TEMPLATE, and CKA_DERIVE_TEMPLATE attributes - allowing any local user or process with socket access to crash the server by sending a single crafted request. No public exploit or active exploitation has been identified at time of analysis, and impact is limited to availability (denial of service) with no confidentiality or integrity consequence.

Heap use-after-free read in libblkid (util-linux) enables unauthenticated local attackers to crash udisks or leak root-process heap data by presenting a crafted block device image during nested partition probing. BSD, Minix, Solaris x86, and UnixWare partition table parsers cache raw pointers into a dynamically allocated partition array; when subsequent partition additions trigger array reallocation, those pointers become stale and dereference freed memory. Because udev and udisks invoke libblkid automatically as root on block-device hot-plug events, USB insertion alone is sufficient to trigger the flaw without any user interaction or authentication. No public exploit identified at time of analysis.

OpenSSH's GSSAPI authentication cleanup routine contains a heap out-of-bounds read (CWE-125) triggered when the auth-indicators array lacks a trailing NULL terminator, allowing a remote unauthenticated attacker to crash the SSH authentication path and deny SSH service availability. Exploitation is constrained by high attack complexity (AC:H) due to the non-default Kerberos/GSSAPI configuration requirement, limiting real-world exposure to a minority of deployments. No active exploitation is confirmed (not in CISA KEV), no public exploit code has been identified, and the impact is restricted to partial availability loss with no confidentiality or integrity consequence.

X11 forwarding session hijacking in OpenSSH enables a local unprivileged attacker sharing a Linux client host to intercept and partially manipulate the victim's forwarded X11 display traffic by squatting on the predictable abstract UNIX domain socket name before the SSH client creates it. Affected deployments span OpenSSH packages across Red Hat Enterprise Linux 6 through 10, Red Hat Hardened Images, and OpenShift Container Platform 4. No public exploit code has been identified at time of analysis, but successful exploitation yields high-confidence access to sensitive X11 session data including keystrokes, window contents, and clipboard material.

Client-side Denial of Service in OpenSSH's Diffie-Hellman Group Exchange implementation allows a malicious SSH server to crash connecting clients running in FIPS mode. When a victim initiates an SSH connection to an attacker-controlled server, the server sends crafted DH-GEX group parameters that trigger a double free (CWE-415) during FIPS known-group validation, terminating the client process. No public exploit code has been identified at time of analysis, and the vulnerability is not listed in CISA KEV; however, the constraint that only FIPS-mode clients are affected limits real-world impact to regulated or government environments.

Insufficient authorization in the Katello ContentUploadsController within Red Hat Satellite 6 permits authenticated users holding only the edit_products permission to query content metadata for repositories belonging to products they have no rights to manage. The flaw, rooted in a missing ActiveRecord scope on repository lookup, allows cross-product content-existence enumeration via the content-upload API - but explicitly does not permit modification, import, or publication of content. No public exploit exists and the vulnerability is not listed in CISA KEV; risk is bounded by the authentication requirement and the limited read-only impact.

Use-after-free memory corruption in GnuTLS's PKCS#11 PIN management function `gnutls_pkcs11_token_set_pin` enables a local low-privileged attacker to crash the process and potentially corrupt memory on systems where PKCS#11 tokens are deployed without a protected authentication path. Affected deployments span Red Hat Enterprise Linux 6 through 10, Red Hat Hardened Images, and Red Hat OpenShift Container Platform 4, as confirmed by Red Hat (reporter) and covered under GnuTLS upstream advisory GNUTLS-SA-2026-04-29-9. No public exploit code has been identified at time of analysis, and the vulnerability is not listed in the CISA KEV catalog.

Heap out-of-bounds read in MIT krb5's LDAP KDB plugin allows a compromised or malicious LDAP backend to crash the KDC or kadmind process, or leak heap memory. The flaw exists in berval2tl_data() within libkdb_ldap and is triggered when the LDAP server returns a krbExtraData attribute with bv_len less than 2, causing an unsigned integer underflow that drives a memcpy of up to 65,534 bytes from a near-zero-length source buffer. Exploitation requires prior control of the LDAP KDB backend server (PR:H, AC:H), constraining real-world risk to insider or supply-chain threat scenarios; no public exploit or CISA KEV listing exists at time of analysis.

Root command injection in dracut's legacy DHCP path allows adjacent-network attackers to execute arbitrary commands inside the initramfs by sending crafted DHCP options (e.g., malicious hostname) that are written unescaped into temporary shell scripts. The flaw affects Red Hat Enterprise Linux 6 through 10, Red Hat Hardened Images, and OpenShift Container Platform 4, granting full system compromise during early boot. No public exploit identified at time of analysis, and EPSS is low (0.16%, 36th percentile), but SSVC rates technical impact as total.

GnuTLS's PKCS#7 padding validation during decryption is not implemented as a constant-time operation, creating a timing side-channel (CWE-208) that remote unauthenticated attackers can exploit to infer padding byte values on CBC-mode cipher suites. Affected deployments include GnuTLS as packaged across Red Hat Enterprise Linux 6 through 10, Red Hat Hardened Images, and Red Hat OpenShift Container Platform 4. Red Hat has issued patch RHSA-2026:20613; no active exploitation is confirmed in CISA KEV, and no public exploit code has been identified, but the network-reachable, no-auth-required attack surface warrants patching on systems handling sensitive encrypted traffic.

Local code execution in Poppler's Splash rendering backend allows attackers to compromise applications that open attacker-supplied PDFs by triggering an integer overflow in tilingPatternFill that produces an undersized heap allocation and a subsequent out-of-bounds write. The flaw affects Poppler as shipped across Red Hat Enterprise Linux 6 through 10 and Red Hat Hardened Images, with impact including arbitrary code execution, information disclosure, or denial of service in the rendering process. No public exploit identified at time of analysis, and the CVSS 7.8 vector requires user interaction to open a malicious PDF.

Command injection in the rpmuncompress utility of RPM allows local attackers to execute arbitrary commands when a victim extracts a maliciously crafted ZIP, 7z, or GEM archive whose top-level folder name contains shell metacharacters. The flaw affects Red Hat Enterprise Linux 6 through 10 and downstream products including OpenShift Container Platform 4, Satellite 6, Red Hat Hardened Images, and Quarkus Native Builder. No public exploit identified at time of analysis, and the issue requires user interaction with an attacker-supplied archive, but successful exploitation yields full code execution under the extracting user's identity.

Memory corruption via an off-by-one error in GnuTLS PKCS#12 bag element handling exposes any application using GnuTLS to remote unauthenticated denial of service - and potentially unspecified further impact - when a crafted PKCS#12 structure is parsed. The CVSS vector (AV:N/AC:L/PR:N/UI:N) confirms exploitation requires no authentication, no user interaction, and no elevated complexity, making internet-exposed services that parse client-supplied PKCS#12 inputs the primary risk surface. No public exploit code exists and the vulnerability is not listed in the CISA KEV catalog at time of analysis.

Certificate validation bypass in GnuTLS (as shipped in Red Hat Enterprise Linux 6 through 10, OpenShift Container Platform 4, and Red Hat Hardened Images) lets a remote attacker defeat hostname verification: when a certificate carries an oversized Subject Alternative Name, the library incorrectly abandons SAN matching and falls back to the legacy Common Name field, accepting certificates it should reject. An attacker positioned to intercept traffic can present such a certificate to impersonate a trusted server and conduct spoofing or man-in-the-middle attacks against TLS clients that rely on GnuTLS. There is no public exploit identified at time of analysis, no CISA KEV listing, and no EPSS score in the provided data.

Improper certificate validation in GnuTLS (CWE-295) lets a remote attacker defeat TLS hostname verification by presenting a certificate that carries URI or SRV Subject Alternative Names, causing GnuTLS to incorrectly fall back to matching the connection's DNS hostname against the certificate's Common Name (CN) and enabling service spoofing or man-in-the-middle interception of sensitive data. The flaw was reported by Red Hat against GnuTLS as shipped in Red Hat Enterprise Linux 6 through 10, OpenShift Container Platform 4, and Red Hat Hardened Images, and carries a CVSS 3.1 base score of 7.1 driven by high integrity impact. No public exploit has been identified at time of analysis and the issue is not listed in CISA KEV; exploitation requires the victim to initiate a connection to attacker-controlled infrastructure (UI:R).

Information disclosure and denial of service in GnuTLS (libgnutls) let a remote, unauthenticated attacker trigger a heap overread against TLS servers that perform legacy RSA key exchange using a private key backed by a PKCS#11 token. By sending an abnormally short premaster secret, the attacker causes the library to read beyond an allocated buffer (CWE-1284), which can leak a small amount of adjacent heap memory and, per the CVSS vector, more strongly impacts availability (A:H). No public exploit has been identified at time of analysis and the issue is not in CISA KEV; EPSS and SSVC data were not provided.

Heap buffer overflow in libsolv allows local attackers to corrupt memory when a vulnerable application processes a maliciously crafted .solv repository metadata file. The flaw stems from insufficient input validation during decompression of attacker-controlled data, enabling information disclosure, control-flow alteration, or denial of service across multiple Red Hat Enterprise Linux releases and SUSE distributions. SSVC marks exploitation as PoC-level with total technical impact, while EPSS remains very low at 0.01%, indicating limited probability of widespread exploitation despite high severity.

Certificate validation in GnuTLS can be bypassed when a certificate chain contains Certificate Authorities with only excluded name constraints followed by CAs with permitted name constraints. Remote attackers can exploit this flaw (CVSS 7.4, AV:N/AC:H) to present invalid certificates that pass validation, enabling man-in-the-middle attacks or service impersonation against TLS-protected communications. The vulnerability affects Red Hat Enterprise Linux versions 6-10, OpenShift Container Platform 4, and Red Hat Hardened Images. No public exploit or active exploitation confirmed at time of analysis, though the technical nature suggests targeted attacks against high-value certificate infrastructure are feasible.

Heap buffer overflow in GnuTLS DTLS handshake allows remote unauthenticated attackers to crash applications or corrupt memory. The vulnerability stems from inconsistent fragment validation in merge_handshake_packet(), where attackers can send crafted DTLS fragments with conflicting message_length values to trigger out-of-bounds writes. Red Hat reported this affecting RHEL 6-10 and OpenShift Container Platform 4. CVSS 7.5 (High) reflects network-accessible denial of service, though memory corruption may enable further exploitation. No EPSS data, KEV status, or POC availability reported at time of analysis, but the remote unauthenticated attack vector (AV:N/PR:N) and low complexity (AC:L) make this a priority for systems using DTLS.

Out-of-bounds read in the GnuTLS DTLS handshake reassembly logic lets remote unauthenticated attackers trigger an integer underflow by sending malformed handshake fragments with zero length and a non-zero offset, enabling information disclosure or denial of service against Red Hat-shipped GnuTLS (RHEL 6 through 10, OpenShift Container Platform 4, and Red Hat Hardened Images). Reported by Red Hat with a vendor patch available and errata released; no public exploit identified at time of analysis, and EPSS is very low (0.04%, 11th percentile) with SSVC exploitation status 'none'. CVSS 9.1 reflects high confidentiality and availability impact over the network at low complexity without authentication.

GnuTLS with OCSP verification enabled incorrectly accepts revoked server certificates when presented with specially crafted multi-record OCSP responses during TLS handshakes, allowing attackers to bypass certificate revocation checks and establish connections to compromised servers. The vulnerability requires high attack complexity and specific OCSP configuration, affecting Red Hat Enterprise Linux 6-10, Red Hat Hardened Images, and OpenShift Container Platform 4. No public exploit code or active exploitation has been identified at the time of analysis.

Certificate name-constraints bypass in GnuTLS allows a remote attacker to craft a leaf certificate whose Subject Alternative Name differs only in letter casing from a constrained dNSName or rfc822Name, causing GnuTLS to accept a certificate that its excludedSubtrees/permittedSubtrees policy should reject. The flaw stems from case-sensitive comparison of name-constraint labels and enables unauthorized access, impersonation, or information disclosure across software (notably Red Hat Enterprise Linux 6-10 and OpenShift Container Platform 4) that relies on GnuTLS for X.509 validation. SSVC notes a public proof-of-concept exists, though EPSS exploitation probability is very low (0.03%, 9th percentile) and the issue is not in CISA KEV.

Heap buffer overflow in GNU Binutils XCOFF linker allows arbitrary code execution when a local user processes a malicious object file. Red Hat Enterprise Linux versions 6 through 10 are confirmed affected via CPE data. CVSS 7.8 reflects local attack vector requiring user interaction (opening/linking the crafted file). No active exploitation confirmed (not in CISA KEV), and no public proof-of-concept identified at time of analysis. Real-world risk depends heavily on whether development workflows involve linking untrusted XCOFF files, which is uncommon outside AIX/PowerPC cross-compilation scenarios.

The readelf utility in binutils is vulnerable to denial of service through two distinct flaws triggered by maliciously crafted ELF files: a resource exhaustion vulnerability (CWE-400) causing out-of-memory conditions and a null pointer dereference (CWE-476) causing segmentation faults. Both vulnerabilities require local access and user interaction to open a malicious file, resulting in the readelf utility crashing or becoming unresponsive. No public exploit code or active exploitation has been identified at the time of analysis.

The readelf utility in binutils is vulnerable to denial of service through null pointer dereference when processing specially crafted ELF files. A local attacker with limited privileges can trigger excessive resource consumption or program crashes by convincing a user to process a malicious ELF binary, affecting Red Hat Enterprise Linux 6, 7, 8, and 10. No public exploit code or active exploitation has been confirmed at this time.

Remote unauthenticated attackers can crash GnuTLS servers by sending malformed TLS handshake messages containing invalid Pre-Shared Key binder values, triggering a NULL pointer dereference. Red Hat Enterprise Linux versions 6-10, OpenShift Container Platform 4, and Red Hat Hardened Images are affected. Vendor patches are available. EPSS score of 0.08% (24th percentile) suggests low current exploitation probability despite network-accessible attack vector. SSVC framework classifies this as automatable with partial technical impact but no known exploitation, making this a medium-priority patching target focused on preventing service disruption rather than data breach.