{"id":"CVE-2026-34181","summary":"PKCS#12 Files with PBMAC1 Are Accepted with Short HMAC Keys","details":"Issue Summary: The PKCS#12 file processing fails to perform sufficient input\nvalidation for files that use Password-Based Message Authentication Code 1\n(PBMAC1) integrity mechanism allowing a certificate and private key forgery.\n\nImpact Summary: An attacker impersonating a user can cause a service reading\nPKCS#12 files to accept forged certificates and private keys with a 1 in 256\nprobability.\n\nIf a service accepting PKCS#12 files is using passwords for authenticating\nthe received files, the attacker can create unencrypted PKCS#12 files that\nuse PBMAC1 authentication that specifies an HMAC key of only one byte, allowing\nthem to craft a file that will be accepted with a 1 in 256 probability.\nThat would then cause the service to accept a certificate and private key\ncontrolled by the attacker.\n\nThe FIPS modules are not affected by this issue, as the affected code is\noutside the OpenSSL FIPS module boundary.","modified":"2026-06-12T12:29:11.192224914Z","published":"2026-06-09T16:03:22.065Z","related":["ALSA-2026:25237","ALSA-2026:25239","CGA-vfrc-p9m8-wf7h"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34181.json","cna_assigner":"openssl","cwe_ids":["CWE-354"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34181.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34181"},{"type":"ADVISORY","url":"https://openssl-library.org/news/secadv/20260609.txt"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/0300eb9ddce7a0895bf301a4b0c03a9da2313a0f"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/79eb76a937e474bb7610a0a3dc57131dc8dc6610"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/85dcbb3abaa4878af5c8fbbe11bce708fcf984a7"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/ec36f2417c4ddd8cabce4b4a60a3d7a7365f2d81"},{"type":"FIX","url":"https://github.com/openssl/security/commit/0300eb9ddce7a0895bf301a4b0c03a9da2313a0f"},{"type":"FIX","url":"https://github.com/openssl/security/commit/79eb76a937e474bb7610a0a3dc57131dc8dc6610"},{"type":"FIX","url":"https://github.com/openssl/security/commit/85dcbb3abaa4878af5c8fbbe11bce708fcf984a7"},{"type":"FIX","url":"https://github.com/openssl/security/commit/ec36f2417c4ddd8cabce4b4a60a3d7a7365f2d81"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/openssl/openssl","events":[{"introduced":"11b7b6ea3b65a584e1d31408ed1bdb139465cffd"},{"fixed":"1e963a8680ec78ad2072792c7a1a71f3c530bd2e"},{"introduced":"7b371d80d959ec9ab4139d09d78e83c090de9779"},{"fixed":"aae016bfd52fcad2bc9657c2c782cfdf73b1ed5f"},{"introduced":"636dfadc70ce26f2473870570bfd9ec352806b1d"},{"fixed":"8cf17aaeb4599f8af87fefd810b5b5fee90fe69e"},{"introduced":"98acb6b02839c609ef5b837794e08d906d965335"},{"fixed":"c5ea1cc227fd60afae8ac4b9438690bbe4888f79"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"4.0.0"},{"fixed":"4.0.1"},{"introduced":"3.6.0"},{"fixed":"3.6.3"},{"introduced":"3.5.0"},{"fixed":"3.5.7"},{"introduced":"3.4.0"},{"fixed":"3.4.6"}]}}],"versions":["openssl-4.0.0","openssl-3.4.5","openssl-3.5.6","openssl-3.6.2","openssl-3.4.4","openssl-3.5.5","openssl-3.6.1","3.4-POST-CLANG-FORMAT-WEBKIT","3.4-PRE-CLANG-FORMAT-WEBKIT","3.5-POST-CLANG-FORMAT-WEBKIT","3.5-PRE-CLANG-FORMAT-WEBKIT","3.6-POST-CLANG-FORMAT-WEBKIT","3.6-PRE-CLANG-FORMAT-WEBKIT","openssl-3.6.0","openssl-3.4.3","openssl-3.5.4","openssl-3.5.3","openssl-3.5.2","openssl-3.4.2","openssl-3.5.1","openssl-3.5.0","openssl-3.4.1","openssl-3.4.0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-34181.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"}]}