{"id":"GHSA-fp7w-m676-w7gc","summary":"social-auth-core Vulnerable to Account Takeover via Identity Binding Flaw in Vend Backend","details":"### Impact\n\nThe Vend OAuth2 backend used only the numeric Vend `user_id` as the social-auth UID.\n\nWhen 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.\n\nThe issue affects applications using the Vend OAuth2 backend with more than one Vend shop.\n\n### Patches\n\nThe issue has been fixed by scoping Vend social-auth UIDs by shop.\n\nUsers should upgrade to a patched version.\n\nFix:\n\n* https://github.com/python-social-auth/social-core/pull/1795\n\n### Workarounds\n\nApplications that cannot upgrade immediately should restrict the Vend OAuth2 backend to a single trusted Vend shop.\n\nIf Vend authentication is not required, the Vend backend can also be disabled by removing it from `SOCIAL_AUTH_AUTHENTICATION_BACKENDS`.\n\nThere is no complete workaround while continuing to allow authentication from multiple Vend shops with the vulnerable backend.\n\n### Credits\n\nReported through GitHub private vulnerability reporting by Liyi Zhou, Ziyue Wang, Strick, Maurice, and Chenchen Yu from the University of Sydney security research team.\n\nReporter references:\n\n* https://lzhou1110.github.io/\n* https://zyy0530.github.io/\n* https://str1ckl4nd.github.io/\n* https://maurice.busystar.org/\n* https://7thparkk.github.io/","aliases":["CVE-2026-57176"],"modified":"2026-09-24T20:15:05.897096234Z","published":"2026-09-24T19:55:57Z","database_specific":{"github_reviewed":true,"github_reviewed_at":"2026-09-24T19:55:57Z","nvd_published_at":"2026-09-24T18:17:14Z","cwe_ids":["CWE-289"],"severity":"MODERATE"},"references":[{"type":"WEB","url":"https://github.com/python-social-auth/social-core/security/advisories/GHSA-fp7w-m676-w7gc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-57176"},{"type":"WEB","url":"https://github.com/python-social-auth/social-core/pull/1795"},{"type":"WEB","url":"https://github.com/python-social-auth/social-core/commit/dee7ad1785877afd355dd6860598823d2631b76e"},{"type":"PACKAGE","url":"https://github.com/python-social-auth/social-core"},{"type":"WEB","url":"https://github.com/python-social-auth/social-core/releases/tag/5.0.0"}],"affected":[{"package":{"name":"social-auth-core","ecosystem":"PyPI","purl":"pkg:pypi/social-auth-core"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.0.0"}]}],"versions":["0.0.1","0.1.0","0.2.0","0.2.1","1.0.0","1.0.1","1.1.0","1.2.0","1.3.0","1.4.0","1.5.0","1.6.0","1.7.0","2.0.0","3.0.0","3.1.0","3.2.0","3.3.0","3.3.1","3.3.2","3.3.3","3.4.0","4.0.2","4.0.3","4.1.0","4.2.0","4.3.0","4.4.0","4.4.1","4.4.2","4.5.0","4.5.1","4.5.2","4.5.3","4.5.4","4.5.5","4.5.6","4.6.0","4.6.1","4.7.0","4.8.0","4.8.1","4.8.2","4.8.3","4.8.4","4.8.5","4.8.6","4.8.7","4.9.0","4.9.1"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-fp7w-m676-w7gc/GHSA-fp7w-m676-w7gc.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N"}]}