CVE-2026-34610

{"id": "CVE-2026-34610", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.9, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 2.2}]}, "published": "2026-04-02T18:16:32.567", "references": [{"url": "https://github.com/smuellerDD/leancrypto/commit/5cdcbe12bd6c3d6e87e969972a580b44a74c3a6a", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/smuellerDD/leancrypto/releases/tag/v1.7.1", "tags": ["Product", "Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/smuellerDD/leancrypto/security/advisories/GHSA-636g-jxv4-v4gr", "tags": ["Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-681"}]}], "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."}], "lastModified": "2026-04-24T13:01:10.780", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:leancrypto:leancrypto:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "EEBE3140-06FC-43FD-B7D3-D96E65CD4B38", "versionEndExcluding": "1.7.1"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}