All vulnerabilities
CVE-2026-57175GHSA-vq6g-g6c7-5f2jPYSEC-2026-4167

social-auth-core has an Improper Authentication issue

python-social-auth social-auth-corepipRuntimes & languages
Open in ThreatlineRecord JSON
CVSS
6.4Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.23%Chance of exploitation activity in the next 30 days, higher than 12% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in5.0.0Fixed versionGitHub
Published24 Sep 2026Updated 5 Oct 2026CVE List

What fixes it

  • 5.0.0social-auth-core, pipGitHub
  • 5.0.0social-auth-core, PyPIOSVpip install "social-auth-core>=5.0.0"

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

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/

Text from GitHub Advisory Database

Affected versions 53

  • social-auth-core, pip< 5.0.0GitHub
  • social-coreaffected: < 5.0.0CVE List
  • social-auth-core, PyPIfrom first release, fixed in 5.0.0OSV
  • social-auth-core, PyPI0.0.1OSV
  • social-auth-core, PyPI0.1.0OSV
  • social-auth-core, PyPI0.2.0OSV
  • social-auth-core, PyPI0.2.1OSV
  • social-auth-core, PyPI1.0.0OSV
  • social-auth-core, PyPI1.0.1OSV
  • social-auth-core, PyPI1.1.0OSV
  • social-auth-core, PyPI1.2.0OSV
  • social-auth-core, PyPI1.3.0OSV
  • social-auth-core, PyPI1.4.0OSV
  • social-auth-core, PyPI1.5.0OSV
  • social-auth-core, PyPI1.6.0OSV
  • social-auth-core, PyPI1.7.0OSV
  • social-auth-core, PyPI2.0.0OSV
  • social-auth-core, PyPI3.0.0OSV
  • social-auth-core, PyPI3.1.0OSV
  • social-auth-core, PyPI3.2.0OSV
  • social-auth-core, PyPI3.3.0OSV
  • social-auth-core, PyPI3.3.1OSV
  • social-auth-core, PyPI3.3.2OSV
  • social-auth-core, PyPI3.3.3OSV
  • social-auth-core, PyPI3.4.0OSV
  • social-auth-core, PyPI4.0.2OSV
  • social-auth-core, PyPI4.0.3OSV
  • social-auth-core, PyPI4.1.0OSV
  • social-auth-core, PyPI4.2.0OSV
  • social-auth-core, PyPI4.3.0OSV
  • social-auth-core, PyPI4.4.0OSV
  • social-auth-core, PyPI4.4.1OSV
  • social-auth-core, PyPI4.4.2OSV
  • social-auth-core, PyPI4.5.0OSV
  • social-auth-core, PyPI4.5.1OSV
  • social-auth-core, PyPI4.5.2OSV
  • social-auth-core, PyPI4.5.3OSV
  • social-auth-core, PyPI4.5.4OSV
  • social-auth-core, PyPI4.5.5OSV
  • social-auth-core, PyPI4.5.6OSV
  • social-auth-core, PyPI4.6.0OSV
  • social-auth-core, PyPI4.6.1OSV
  • social-auth-core, PyPI4.7.0OSV
  • social-auth-core, PyPI4.8.0OSV
  • social-auth-core, PyPI4.8.1OSV
  • social-auth-core, PyPI4.8.2OSV
  • social-auth-core, PyPI4.8.3OSV
  • social-auth-core, PyPI4.8.4OSV
  • social-auth-core, PyPI4.8.5OSV
  • social-auth-core, PyPI4.8.6OSV
  • social-auth-core, PyPI4.8.7OSV
  • social-auth-core, PyPI4.9.0OSV
  • social-auth-core, PyPI4.9.1OSV

References 6