{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-34610", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-03-30T17:15:52.500Z", "datePublished": "2026-04-02T17:54:53.250Z", "dateUpdated": "2026-04-02T17:54:53.250Z"}, "containers": {"cna": {"title": "leancrypto: Integer truncation in X.509 name parser enables certificate identity impersonation", "problemTypes": [{"descriptions": [{"cweId": "CWE-681", "lang": "en", "description": "CWE-681: Incorrect Conversion between Numeric Types", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.9, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/smuellerDD/leancrypto/security/advisories/GHSA-636g-jxv4-v4gr", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/smuellerDD/leancrypto/security/advisories/GHSA-636g-jxv4-v4gr"}, {"name": "https://github.com/smuellerDD/leancrypto/commit/5cdcbe12bd6c3d6e87e969972a580b44a74c3a6a", "tags": ["x_refsource_MISC"], "url": "https://github.com/smuellerDD/leancrypto/commit/5cdcbe12bd6c3d6e87e969972a580b44a74c3a6a"}, {"name": "https://github.com/smuellerDD/leancrypto/releases/tag/v1.7.1", "tags": ["x_refsource_MISC"], "url": "https://github.com/smuellerDD/leancrypto/releases/tag/v1.7.1"}], "affected": [{"vendor": "smuellerDD", "product": "leancrypto", "versions": [{"version": "< 1.7.1", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-04-02T17:54:53.250Z"}, "descriptions": [{"lang": "en", "value": "The leancrypto library is a cryptographic library that exclusively contains only PQC-resistant cryptographic algorithms. Prior to version 1.7.1, lc_x509_extract_name_segment() casts size_t vlen to uint8_t when storing the Common Name (CN) length. An attacker who crafts a certificate with CN = victim's CN + 256 bytes padding gets cn_size = (uint8_t)(256 + N) = N, where N is the victim's CN length. The first N bytes of the attacker's CN are the victim's identity. After parsing, the attacker's certificate has an identical CN to the victim's \u2014 enabling identity impersonation in PKCS#7 verification, certificate chain matching, and code signing. This issue has been patched in version 1.7.1."}], "source": {"advisory": "GHSA-636g-jxv4-v4gr", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "The leancrypto library is a cryptographic library that exclusively contains only PQC-resistant cryptographic algorithms. Prior to version 1.7.1, lc_x509_extract_name_segment() casts size_t vlen to uint8_t when storing the Common Name (CN) length. An attacker who crafts a certificate with CN = victim's CN + 256 bytes padding gets cn_size = (uint8_t)(256 + N) = N, where N is the victim's CN length. The first N bytes of the attacker's CN are the victim's identity. After parsing, the attacker's certificate has an identical CN to the victim's \u2014 enabling identity impersonation in PKCS#7 verification, certificate chain matching, and code signing. This issue has been patched in version 1.7.1."}], "id": "CVE-2026-34610", "lastModified": "2026-04-02T18:16:32.567", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.9, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-04-02T18:16:32.567", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/smuellerDD/leancrypto/commit/5cdcbe12bd6c3d6e87e969972a580b44a74c3a6a"}, {"source": "security-advisories@github.com", "url": "https://github.com/smuellerDD/leancrypto/releases/tag/v1.7.1"}, {"source": "security-advisories@github.com", "url": "https://github.com/smuellerDD/leancrypto/security/advisories/GHSA-636g-jxv4-v4gr"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-681"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}