CVE-2026-115910
Python Social Auth: OpenID Connect nonce is not bound to the browser session, so a stolen authorization code logs the attacker in as the victim
Python Social Auth is a social authentication and registration mechanism. Prior to 6.2.0, OpenIdConnectAuth in social_core/backends/open_id_connect.py uses get_and_store_nonce to place the OpenID Connect nonce in a shared OpenIdConnectAssociation table, and get_nonce and validate_claims verify only that the nonce exists and has not expired rather than binding it to the browser session and OAuth state that initiated the login. An attacker who obtains a victim's unused authorization code can start a separate login to obtain valid state for the attacker's browser, submit the victim's code with that state, and pass nonce validation because the victim nonce is globally available. With DEFAULT_USE_PKCE disabled in the default OpenIdConnectAuth configuration, the attacker can be logged in as the victim. This issue is fixed in version 6.2.0.
- Affected
- python-social-auth · social-core
- CVSS v3.1 GITHUB
- 6.8 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - EPSS
- 0.16% chance of exploitation in the next 30 days, 5th percentile
- Published
- 2026-10-26
Proof-of-concept exploits (1)
CVE references
- python-social-auth/social-core/commit/c2f2ae4663bef19ee8b07f2cf5a2344f9155d826REFERENCE
- python-social-auth/social-core/pull/2141REFERENCE
- python-social-auth/social-core/releases/tag/6.2.0REFERENCE
- python-social-auth/social-core/security/advisories/GHSA-h2r5-x5m7-3935REFERENCE