{"api_version":"1","generated_at":"2026-04-23T11:35:24+00:00","cve":"CVE-2026-34610","urls":{"html":"https://cve.report/CVE-2026-34610","api":"https://cve.report/api/cve/CVE-2026-34610.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-34610","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-34610"},"summary":{"title":"leancrypto: Integer truncation in X.509 name parser enables certificate identity impersonation","description":"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. 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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 — enabling identity impersonation in PKCS#7 verification, certificate chain matching, and code signing. This issue has been patched in version 1.7.1.","Type":"Description","Title":"leancrypto: Integer truncation in X.509 name parser enables cert"}]}}}