{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-5500", "assignerOrgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27", "state": "PUBLISHED", "assignerShortName": "wolfSSL", "dateReserved": "2026-04-03T15:33:05.734Z", "datePublished": "2026-04-10T03:10:25.671Z", "dateUpdated": "2026-04-10T13:42:28.091Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27", "shortName": "wolfSSL", "dateUpdated": "2026-04-10T03:10:25.671Z" }, "title": "Improper Validation of AES-GCM Authentication Tag Length in PKCS#7 Envelope Allows Authentication Bypass", "problemTypes": [ { "descriptions": [ { "lang": "en", "cweId": "CWE-20", "description": "CWE-20 Improper input validation", "type": "CWE" } ] } ], "affected": [ { "vendor": "wolfSSL", "product": "wolfSSL", "modules": [ "wc_PKCS7_DecodeAuthEnvelopedData" ], "programFiles": [ "wolfcrypt/src/pkcs7.c" ], "versions": [ { "status": "affected", "version": "0", "lessThanOrEqual": "5.9.0", "versionType": "semver" } ], "defaultStatus": "unaffected" } ], "descriptions": [ { "lang": "en", "value": "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.", "supportingMedia": [ { "type": "text/html", "base64": false, "value": "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." } ] } ], "references": [ { "url": "https://github.com/wolfSSL/wolfssl/pull/10102" } ], "metrics": [ { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV4_0": { "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "HIGH", "baseScore": 8.7, "vectorString": "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" } } ], "credits": [ { "lang": "en", "value": "Calif.io in collaboration with Claude and Anthropic Research", "type": "finder" } ], "source": { "discovery": "EXTERNAL" }, "x_generator": { "engine": "Vulnogram 1.0.1" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-04-10T13:42:21.317016Z", "id": "CVE-2026-5500", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-04-10T13:42:28.091Z" } } ] } }