{"id":"CVE-2026-57179","aliases":["GHSA-vqg6-3fw6-j9jg","PYSEC-2026-4168"],"url":"https://o3.security/vulnerability/CVE-2026-57179","summary":"social-auth-core has a Session Fixation issue","details":"### Impact\n\nThe partial-pipeline resume mechanism accepted `partial_token` as a bearer credential without binding it to the browser session that created it.\n\nApplications using resumable partial pipeline steps could allow an attacker to start an authentication flow, obtain a valid partial token and verification data, and cause a victim's browser to resume that attacker-controlled flow. This could authenticate the victim's browser as the attacker's account.\n\nThe issue affects applications using partial pipeline steps such as `mail_validation` or custom steps decorated with `@partial`.\n\n### Patches\n\nThe issue has been fixed by binding partial pipeline resumes to the originating browser session.\n\nUsers should upgrade to a patched version.\n\nFix:\n\n* https://github.com/python-social-auth/social-core/pull/1816\n* https://github.com/python-social-auth/social-docs/pull/444\n* https://github.com/python-social-auth/social-app-django/pull/1009\n\n### Workarounds\n\nApplications that cannot upgrade immediately should disable resumable partial pipeline steps, including `mail_validation` and custom steps decorated with `@partial`.\n\nIf those flows are required, applications should avoid accepting partial resume links from untrusted contexts until a patched version can be deployed.\n\nThere is no complete workaround while continuing to use the vulnerable partial-pipeline resume mechanism.\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/","published":"2026-09-24T17:27:00.152Z","modified":"2026-10-21T02:58:44.720175130Z","cvss":{"score":4.2,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"PyPI","name":"social-auth-core","fixedVersion":"5.0.0"}],"fix":{"url":"https://github.com/python-social-auth/social-core/pull/1816","label":"python-social-auth/social-core#1816"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57179.json"},{"type":"ADVISORY","url":"https://github.com/python-social-auth/social-core/security/advisories/GHSA-vqg6-3fw6-j9jg"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-57179"},{"type":"WEB","url":"https://github.com/python-social-auth/social-core/pull/1816"},{"type":"WEB","url":"https://github.com/python-social-auth/social-core/commit/0418782454ac7bbc6a9230ea21f7f5066fe89686"},{"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T02:58:44.720175130Z"}}