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

Published Oct 26, 2026 CVSS 3.1 · 6.8 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-h2r5-x5m7-3935 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
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Python-social-auth
Python-social-auth social-core
Vendors & Products Python-social-auth
Python-social-auth social-core
Type Values Removed Values Added
Description 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.
Title 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
Weaknesses CWE-345
CWE-384
References
Metrics cvssV3_1

{'score': 6.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 31, 2026, 1:34 AM
Reserved
Oct 23, 2026, 8:21 PM
Status
Awaiting Analysis
Published
Oct 26, 2026, 5:17 PM
Modified
Oct 31, 2026, 2:17 AM
Severity
Moderate
Public date
Oct 26, 2026, 4:44 PM