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{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,5.9.0]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "wolfSSL", "source": "cna", "vendor": "wolfSSL"}, "product": "wolfssl", "vendor": "wolfssl"}], "analysis": {"en": {"generated_at": "2026-04-10T04:21:14.768819+00:00", "value": {"mitigation_remediation": ["Apply the latest wolfSSL patch that addresses the tag length check, as referenced in PR\u00a010102", "If an update is not yet possible, avoid accepting PKCS#7 enveloped data from untrusted sources or implement a manual tag length verification routine before decryption", "Monitor traffic and logs for anomalies that could indicate an attempt to truncate authentication tags"], "summary": {"action": "Immediate Patch", "impact": "Authentication Bypass via AES\u2011GCM tag truncation"}, "threat_synthesis": {"affected_systems": "wolfSSL software that implements the PKCS#7 envelope decoding routine is affected. The specific version is not listed, so any release that includes the vulnerable wc_PKCS7_DecodeAuthEnvelopedData implementation may be impacted.", "description_and_impact": "The flaw resides in wc_PKCS7_DecodeAuthEnvelopedData, which omits a lower bound check on the AES\u2011GCM authentication tag length. An attacker can truncate the MAC field from the proper 16 bytes to 1 byte, reducing the tag verification probability from 2\u207b\u00b9\u00b2\u2078 to 2\u207b\u2078 and allowing the encrypted data to be processed without authenticating it. This constitutes a bypass of the integrity check and enables unauthorized disclosure of encrypted secrets.", "risk_and_exploitability": "The CVSS score of 8.7 indicates high severity. Although exact EPSS data is unavailable, the vulnerability involves a known denial of verification and is not listed in CISA's KEV catalogue, suggesting it is not yet widely exploited. The likely attack vector is a man\u2011in\u2011the\u2011middle positioned on the channel carrying PKCS#7 enveloped data, capable of truncating the MAC field. Because the bug removes a critical integrity check, successful exploitation would give an attacker unauthorized access to the decrypted payload."}}}}, "created": "2026-04-10T08:35:53.574344+00:00", "updated": "2026-04-10T09:26:55.310335+00:00", "vendors": ["wolfssl", "wolfssl$PRODUCT$wolfssl"]}