GitHub Advisoryadvisory · PyPI
GHSA-vq6g-g6c7-5f2j social-auth-core has an Improper Authentication issue
MEDIUM
Official page ↗
- Aliases
- CVE-2026-57175
- Ecosystem
- PyPI
- Packages
- social-auth-core
- Severity
- Moderate
- CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
- Weaknesses
- CWE-287
- Reviewed
- 2026-09-24
Affected packages
• PyPI social-auth-core: < 5.0.0 → fixed in 5.0.0
Description
Impact
The SAML backend accepted SAML responses on the Assertion Consumer Service endpoint without verifying that they matched a previously issued `AuthnRequest`.
Applications using SAML account association could allow an attacker with a valid account on a trusted IdP to link the attacker's SAML identity to a logged-in victim's local account. The attacker could then authenticate through SAML and gain access to the victim's account.
The issue affects applications using the SAML backend together with authenticated account association.
Patches
The issue has been fixed by validating SAML responses against stored `AuthnRequest` IDs.
Users should upgrade to a patched version.
Fix:
• https://github.com/python-social-auth/social-core/pull/1794
Workarounds
Applications that cannot upgrade immediately should disable SAML account association for already authenticated users.
If SAML login is not required, the SAML backend can also be disabled by removing it from `SOCIAL_AUTH_AUTHENTICATION_BACKENDS`.
There is no complete workaround while continuing to allow vulnerable SAML account association.
Credits
Reported through GitHub private vulnerability reporting by Liyi Zhou, Ziyue Wang, Strick, Maurice, and Chenchen Yu from the University of Sydney security research team.
Reporter references:
• https://lzhou1110.github.io/
• https://zyy0530.github.io/
• https://str1ckl4nd.github.io/
• https://maurice.busystar.org/
• https://7thparkk.github.io/
Related
Alias · CVE (1)
- CVE-2026-57175 Python Social Auth is a social authentication/registration mechanism. vulnerability
Weakness · CWE (1)
- CWE-287 Improper Authentication weakness
References
- https://github.com/python-social-auth/social-core/security/advisories/GHSA-vq6g-g6c7-5f2j web
- https://nvd.nist.gov/vuln/detail/CVE-2026-57175 advisory
- https://github.com/python-social-auth/social-core/pull/1794 web
- https://github.com/python-social-auth/social-core/commit/5c72f71125bc60e4411f09e2a9f998de5da7fcb6 web
- https://github.com/python-social-auth/social-core package
- https://github.com/python-social-auth/social-core/releases/tag/5.0.0 web