CVE-2026-34181

Name	CVE-2026-34181
Description	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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
openssl (PTS)	bullseye	1.1.1w-0+deb11u1	fixed
	bullseye (security)	1.1.1w-0+deb11u7	fixed
	bookworm	3.0.20-1~deb12u1	fixed
	bookworm (security)	3.0.20-1~deb12u2	fixed
	trixie	3.5.6-1~deb13u1	vulnerable
	trixie (security)	3.5.6-1~deb13u2	fixed
	forky, sid	3.6.2-1	vulnerable

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version
openssl	source	bullseye	(not affected)
openssl	source	bookworm	(not affected)
openssl	source	trixie	3.5.6-1~deb13u2
openssl	source	(unstable)	(unfixed)

Notes

[bookworm] - openssl <not-affected> (Vulnerable code not present)
[bullseye] - openssl <not-affected> (Vulnerable code not present)
https://openssl-library.org/news/secadv/20260609.txt