EUVD-2026-21293
GHSA-m77r-vqw2-hffx
Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Lifecycle Timeline
4DescriptionCVE.org
wolfSSL's wc_PKCS7_DecodeAuthEnvelopedData() does not properly sanitize the AES-GCM authentication tag length received and has no lower bounds check. A man-in-the-middle can therefore truncate the mac field from 16 bytes to 1 byte, reducing the tag check from 2⁻¹²⁸ to 2⁻⁸.
AnalysisAI
Man-in-the-middle attackers can truncate AES-GCM authentication tags in wolfSSL's PKCS7 AuthEnvelopedData processing from 16 bytes to 1 byte, degrading cryptographic integrity verification from 2⁻¹²⁸ to 2⁻⁸ probability. Affects wolfSSL versions through 5.9.0 due to missing lower bounds validation in wc_PKCS7_DecodeAuthEnvelopedData(). Unauthenticated network-based attack enables high-severity integrity bypass without user interaction. No public exploit identified at time of analysis.
Technical ContextAI
Root cause is CWE-20 improper input validation in wc_PKCS7_DecodeAuthEnvelopedData() function. Missing lower bounds check on GCM tag length parameter allows acceptance of cryptographically weak 8-bit tags versus standard 128-bit tags, fundamentally undermining authenticated encryption guarantees in PKCS#7 envelope processing.
RemediationAI
Upstream fix available via GitHub pull request #10102; released patched version not independently confirmed at time of analysis. Organizations should monitor wolfSSL security advisories at https://www.wolfssl.com/docs/security-vulnerabilities/ for official release announcements exceeding version 5.9.0. Immediate workaround: disable PKCS#7 AuthEnvelopedData processing in wolfSSL configurations if not operationally required, or implement additional application-layer integrity verification. Network controls: deploy TLS inspection to detect abnormally short GCM tags in PKCS#7 payloads. Reference implementation fix available at https://github.com/wolfSSL/wolfssl/pull/10102. Prioritize patching for internet-facing services processing PKCS#7 encrypted data from untrusted sources.
wolfSSL prior to version 3.12.2 provides a weak Bleichenbacher oracle when any TLS cipher suite using RSA key exchange i
A specially crafted x509 certificate can cause a single out of bounds byte overwrite in wolfSSL through 3.10.2 resulting
wolfSSL (formerly CyaSSL) before 3.6.8 allows remote attackers to cause a denial of service (resource consumption or tra
In wolfSSL before 5.5.1, malicious clients can cause a buffer overflow during a TLS 1.3 handshake. Rated high severity (
An issue was discovered in wolfSSL before 5.5.0. Rated high severity (CVSS 7.5), this vulnerability is remotely exploita
wolfSSL 4.3.0 has mulmod code in wc_ecc_mulmod_ex in ecc.c that does not properly resist timing side-channel attacks. Ra
In wolfSSL 4.1.0 through 4.2.0c, there are missing sanity checks of memory accesses in parsing ASN.1 certificate data wh
An issue was discovered in wolfSSL before 4.5.0, when single precision is not employed. Rated high severity (CVSS 7.0).
wolfSSL before 4.5.0 mishandles TLS 1.3 server data in the WAIT_CERT_CR state, within SanityCheckTls13MsgReceived() in t
wolfSSL (formerly CyaSSL) before 3.6.8 does not properly handle faults associated with the Chinese Remainder Theorem (CR
An issue was discovered in wolfSSL before 5.5.0 (when --enable-session-ticket is used); however, only version 5.3.0 is e
wolfSSL 4.6.x through 4.7.x before 4.8.0 does not produce a failure outcome when the serial number in an OCSP request di
Same weakness CWE-20 – Improper Input Validation
View allSame technique Information Disclosure
View allShare
External POC / Exploit Code
Leaving vuln.today