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(). …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Remote unauthenticated attacker performing man-in-the-middle attack on wolfSSL PKCS#7 authenticated enveloped data decoding. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | CVSS 8.7 reflects high integrity impact from cryptographic weakening. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | Attacker positioned for network interception modifies wc_PKCS7_DecodeAuthEnvelopedData() authentication tag from 16 bytes to 1 byte in transit. Receiver accepts truncated tag, reducing forgery detection from 2⁻¹²⁸ to 2⁻⁸ probability. … |
| Remediation | Upstream fix available via GitHub pull request #10102; released patched version not independently confirmed at time of analysis. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours: Inventory all applications and systems using wolfSSL, specifically identifying those processing PKCS7 AuthEnvelopedData structures; communicate findings to application owners. …
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