CVE-2026-49272

Name	CVE-2026-49272
Description	OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. From 3.3.0 until 4.0.1, OAuthLib's RFC 8628 device workflow does not require DeviceCodeGrant.validate_token_request to check that the device_code parameter is present and valid. A caller whose client request is accepted by the configured validator and who knows a valid client ID enabled for the device workflow can submit a missing or bogus device code to the token endpoint and obtain a bearer token without completing device authorization. This issue is fixed in version 4.0.1.
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	1153277

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
python-oauthlib (PTS)	bookworm	3.2.2-1	vulnerable
	trixie	3.2.2-3	vulnerable
	forky, sid	3.3.1-2	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
python-oauthlib	source	(unstable)	(unfixed)			1153277

Notes

https://github.com/oauthlib/oauthlib/security/advisories/GHSA-3jp2-3mrg-2vxc
https://github.com/oauthlib/oauthlib/pull/954
Fixed by: https://github.com/oauthlib/oauthlib/commit/77a5f1c8ce00da2b0b8c5f6e9cc129920085f114 (v4.0.1)