CVE-2026-57177: social-auth-core has Login CSRF via Missing State Parameter in LoginRadius Backend
Impact
The LoginRadius backend did not validate OAuth state during the authentication flow.
Applications using this backend were vulnerable to login CSRF. An attacker could cause a victim's browser session to complete authentication using an attacker-controlled LoginRadius token, making the victim authenticated as the attacker's LoginRadius identity.
The issue affects only applications using the LoginRadius backend.
Patches
The issue has been fixed by enabling callback state validation for the LoginRadius backend.
Users should upgrade to a patched version.
Fix:
https://github.com/python-social-auth/social-core/pull/1808
Workarounds
Applications that cannot upgrade immediately should disable the LoginRadius backend by removing it from SOCIALAUTHAUTHENTICATIONBACKENDS.
There is no complete workaround while continuing to use the vulnerable backend.
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/
Other sources
Python Social Auth is a social authentication/registration mechanism. Prior to version 5.0.0, the LoginRadius backend did not validate OAuth state during the authentication flow. Applications using this backend were vulnerable to login CSRF. An attacker could cause a victim's browser session to complete authentication using an attacker-controlled LoginRadius token, making the victim authenticated as the attacker's LoginRadius identity. The issue affects only applications using the LoginRadius backend. The issue has been fixe in version 5.0.0 by enabling callback state validation for the LoginRadius backend.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
pip/social-auth-coreto a version that resolves this vulnerability.Fixed in 5.0.0 - Upgrade
Upgrade
social-auth-coreto a version that resolves this vulnerability.Fixed in 5.0.0 - Configuration
Disable the LoginRadius backend by removing it from SOCIAL_AUTH_AUTHENTICATION_BACKENDS if upgrading is not immediately possible.
Python Social Auth SOCIAL_AUTH_AUTHENTICATION_BACKENDS = Remove the LoginRadius backend
Event History
Frequently Asked Questions
Which deployments are affected?
Only applications that use the LoginRadius backend in social-auth-core are affected. Other social-auth-core backends are not identified as affected by this issue.
What does an attacker need to exploit this?
An attacker needs to induce a victim to complete an authentication flow in their browser using an attacker-controlled LoginRadius token. The victim must interact with the flow; no prior privileges are required.
What is the impact of successful exploitation?
The victim's browser session can become authenticated as the attacker's LoginRadius identity. This is a login CSRF issue that affects integrity, not confidentiality or availability.
What should teams do if they use LoginRadius?
Upgrade social-auth-core to version 5.0.0 or later, which enables callback state validation for the LoginRadius backend. The provided data does not describe an alternative mitigation for deployments that cannot upgrade immediately.