{"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":"2026-07-26T05:11:41.771336Z","published":"2026-06-09T16:03:22.065Z","related":["ALSA-2026:25237","ALSA-2026:25239","CGA-vfrc-p9m8-wf7h","SUSE-SU-2026:2648-1"],"database_specific":{"cna_assigner":"openssl","cwe_ids":["CWE-354"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34181.json"},"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"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/openssl/openssl","events":[{"introduced":"98acb6b02839c609ef5b837794e08d906d965335"},{"fixed":"c5ea1cc227fd60afae8ac4b9438690bbe4888f79"},{"introduced":"636dfadc70ce26f2473870570bfd9ec352806b1d"},{"fixed":"8cf17aaeb4599f8af87fefd810b5b5fee90fe69e"},{"introduced":"7b371d80d959ec9ab4139d09d78e83c090de9779"},{"fixed":"aae016bfd52fcad2bc9657c2c782cfdf73b1ed5f"},{"introduced":"11b7b6ea3b65a584e1d31408ed1bdb139465cffd"},{"fixed":"0300eb9ddce7a0895bf301a4b0c03a9da2313a0f"},{"fixed":"79eb76a937e474bb7610a0a3dc57131dc8dc6610"},{"fixed":"85dcbb3abaa4878af5c8fbbe11bce708fcf984a7"},{"fixed":"ec36f2417c4ddd8cabce4b4a60a3d7a7365f2d81"}],"database_specific":{"cpe":["cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*","cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*"],"extracted_events":[{"introduced":"3.4.0"},{"fixed":"3.4.6"},{"introduced":"3.5.0"},{"fixed":"3.5.7"},{"introduced":"3.6.0"},{"fixed":"3.6.3"},{"introduced":"4.0.0-NA"},{"last_affected":"4.0.0-NA"}],"source":["CPE_RANGE","CPE_STRING","REFERENCES"]}}],"versions":["4.0.0-NA","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/cve-osv-conversion/osv-output/CVE-2026-34181.json","vanir_signatures_modified":"2026-07-26T05:11:41Z","vanir_signatures":[{"deprecated":false,"digest":{"length":1300,"function_hash":"315812236523225321135455598472506362094"},"id":"CVE-2026-34181-10a23314","signature_type":"Function","signature_version":"v1","source":"https://github.com/openssl/openssl/commit/85dcbb3abaa4878af5c8fbbe11bce708fcf984a7","target":{"file":"crypto/pkcs12/p12_mutl.c","function":"PBMAC1_PBKDF2_HMAC"}},{"deprecated":false,"digest":{"length":1300,"function_hash":"315812236523225321135455598472506362094"},"id":"CVE-2026-34181-179c423c","signature_type":"Function","signature_version":"v1","source":"https://github.com/openssl/openssl/commit/ec36f2417c4ddd8cabce4b4a60a3d7a7365f2d81","target":{"file":"crypto/pkcs12/p12_mutl.c","function":"PBMAC1_PBKDF2_HMAC"}},{"target":{"function":"PBMAC1_PBKDF2_HMAC","file":"crypto/pkcs12/p12_mutl.c"},"deprecated":false,"digest":{"function_hash":"76940837782890555457350612104326271031","length":1377},"id":"CVE-2026-34181-30fef3db","signature_type":"Function","signature_version":"v1","source":"https://github.com/openssl/openssl/commit/0300eb9ddce7a0895bf301a4b0c03a9da2313a0f"},{"id":"CVE-2026-34181-4b6dc014","signature_type":"Line","signature_version":"v1","source":"https://github.com/openssl/openssl/commit/85dcbb3abaa4878af5c8fbbe11bce708fcf984a7","target":{"file":"crypto/pkcs12/p12_mutl.c"},"deprecated":false,"digest":{"line_hashes":["279241462574763049619469167939590085965","124667758924786016762543144623160633643","19236051917043646048645916126187618535","231367928065682063288219806662093847496","49790318440299563265754245713723343566","277242367734218736396726487976444044573","147519211957771243650362882755125492373"],"threshold":0.9}},{"target":{"file":"crypto/pkcs12/p12_mutl.c"},"deprecated":false,"digest":{"line_hashes":["279241462574763049619469167939590085965","124667758924786016762543144623160633643","19236051917043646048645916126187618535","231367928065682063288219806662093847496","49790318440299563265754245713723343566","277242367734218736396726487976444044573","147519211957771243650362882755125492373"],"threshold":0.9},"id":"CVE-2026-34181-caddfd8e","signature_type":"Line","signature_version":"v1","source":"https://github.com/openssl/openssl/commit/ec36f2417c4ddd8ca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