CVE-2026-34181

Issue Summary: The PKCS#12 file processing fails to perform sufficient input validation for files that use Password-Based Message Authentication Code 1 (PBMAC1) integrity mechanism allowing a certificate and private key forgery. Impact Summary: An attacker impersonating a user can cause a service reading PKCS#12 files to accept forged certificates and private keys with a 1 in 256 probability. If a service accepting PKCS#12 files is using passwords for authenticating the received files, the attacker can create unencrypted PKCS#12 files that use PBMAC1 authentication that specifies an HMAC key of only one byte, allowing them to craft a file that will be accepted with a 1 in 256 probability. That would then cause the service to accept a certificate and private key controlled by the attacker. The FIPS modules are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/openssl/openssl/commit/0300eb9ddce7a0895bf301a4b0c03a9da2313a0f	Patch
https://github.com/openssl/openssl/commit/79eb76a937e474bb7610a0a3dc57131dc8dc6610	Patch
https://github.com/openssl/openssl/commit/85dcbb3abaa4878af5c8fbbe11bce708fcf984a7	Patch
https://github.com/openssl/openssl/commit/ec36f2417c4ddd8cabce4b4a60a3d7a7365f2d81	Patch
https://openssl-library.org/news/secadv/20260609.txt	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:openssl:openssl::::::::
	cpe:2.3:a:openssl:openssl::::::::
	cpe:2.3:a:openssl:openssl::::::::
	cpe:2.3:a:openssl:openssl:4.0.0:-::::::

History

No history.

Information

Published : 2026-06-09 17:17

Updated : 2026-07-23 08:10

NVD link : CVE-2026-34181

Mitre link : CVE-2026-34181

CVE.ORG link : CVE-2026-34181

JSON object : View

Products Affected

openssl

openssl

CWE

CWE-354

Improper Validation of Integrity Check Value

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Eso entonces har\u00eda que el servicio acepte un certificado y una clave privada controlados por el atacante.\n\nLos m\u00f3dulos FIPS no se ven afectados por este problema, ya que el c\u00f3digo afectado est\u00e1 fuera del l\u00edmite del m\u00f3dulo FIPS de OpenSSL."}], "lastModified": "2026-07-23T08:10:00.137", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BF7E21E7-AEC0-4882-B1F1-2D056B506F22", "versionEndExcluding": "3.4.6", "versionStartIncluding": "3.4.0"}, {"criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6B6B9930-C549-4D88-9784-AF32CCDDB87A", "versionEndExcluding": "3.5.7", "versionStartIncluding": "3.5.0"}, {"criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D41B3C45-EC73-4DC8-989D-B2E2792E102F", "versionEndExcluding": "3.6.3", "versionStartIncluding": "3.6.0"}, {"criteria": "cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6E881B9A-1A0A-4BC0-8160-20C00561167D"}], "operator": "OR"}]}], "sourceIdentifier": "openssl-security@openssl.org"}