CVE-2026-57176

Name	CVE-2026-57176
Description	Python Social Auth is a social authentication/registration mechanism. Prior to version 5.0.0, the Vend OAuth2 backend used only the numeric Vend user_id as the social-auth UID. When multiple Vend shops authenticate through the same application, users from different shops with the same internal Vend user ID could collide in the social-auth association table. A user from one shop could then be authenticated as the local account previously associated with the same numeric user ID from another shop. The issue affects applications using the Vend OAuth2 backend with more than one Vend shop. Version 5.0.0 patches the issue.
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
social-auth-core (PTS)	bookworm	4.3.0-1	vulnerable
	trixie	4.6.1-1	vulnerable
	forky, sid	5.1.1-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
social-auth-core	source	(unstable)	5.0.2-1

Notes

https://github.com/python-social-auth/social-core/security/advisories/GHSA-fp7w-m676-w7gc
https://github.com/python-social-auth/social-core/pull/1795
Fixed by: https://github.com/python-social-auth/social-core/commit/dee7ad1785877afd355dd6860598823d2631b76e (5.0.0)