CVE-2026-84185

Name	CVE-2026-84185
Description	A flaw was found in the jwcrypto library, which is used for implementing Javascript Object Signing and Encryption (JOSE) standards. The issue occurs when the library verifies a General JSON Serialization JWS using a set of keys. Due to a coding error, the library fails to correctly identify the specific key ID (kid) and may instead accept a signature made by any valid key in the set. This can allow an attacker with a valid key to bypass authorization checks in applications that rely on the key ID to identify specific tenants or users.
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)
Debian Bugs	1146875

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
python-jwcrypto (PTS)	bookworm	1.1.0-1+deb12u1	fixed
	trixie	1.5.6-1.1~deb13u1	vulnerable
	forky, sid	1.5.6-1.2	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
python-jwcrypto	source	bookworm	(not affected)
python-jwcrypto	source	(unstable)	(unfixed)			1146875

Notes

[trixie] - python-jwcrypto <no-dsa> (Minor issue)
[bookworm] - python-jwcrypto <not-affected> (Vulnerable code introduced later)
https://bugzilla.redhat.com/show_bug.cgi?id=2526729
https://github.com/latchset/jwcrypto/security/advisories/GHSA-wwmx-rghj-gq83
Fixed by: https://github.com/latchset/jwcrypto/commit/268f4bc5d46e05393fecbd2854074b11ab20cd65 (v1.6.0)
Introduced by: https://github.com/latchset/jwcrypto/commit/e795a1375b948c06cf288ce64178997c2074d3c0 (v1.3.0)