CVE-2026-114618

Name	CVE-2026-114618
Description	Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.0, the default RFC 7523 JWTBearerGrant.get_audiences() returns an empty list, causing JWTBearerGrant.verify_claims() to require only that an aud claim exists without matching the current authorization server. An attacker holding a legitimate assertion for another service can present it to a server that shares the signing key and uses the default grant, obtaining an access token across a trust boundary. Implementations that override get_audiences() with the server's valid audience identifiers are not affected. This issue is fixed in version 1.9.0.
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
python-authlib (PTS)	bookworm	1.2.0-1+deb12u1	vulnerable
	bookworm (security)	1.2.0-1+deb12u2	vulnerable
	trixie	1.6.0-1+deb13u1	vulnerable
	forky, sid	1.7.2-2	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
python-authlib	source	(unstable)	(unfixed)

Notes

https://github.com/authlib/authlib/security/advisories/GHSA-fch4-3c6x-j4gc
https://github.com/authlib/authlib/pull/945
Fixed by: https://github.com/authlib/authlib/commit/e3bd41cb29dcfee434453b135ffb487884baeedf (v1.9.0)