Auth bypass in Pallets-Eco Flask-Security-Too

CVE-2026-46715

Flask-Security-Too allows users to add security features to their Flask applicationa. Version 5.8.0's OAuth reauthentication flow can mark a session as fresh after verifying an OAuth account that belongs to a different user. If an attacker can operate an already-authenticated but stale victim session, they can complete OAuth verification using their own OAuth identity. The victim session is then treated as recently reauthenticated, allowing freshness-protected account actions to proceed. Version 5.8.1 contains a fix for this issue.

Vulnerability class: Broken Authentication

EPSS: 0.005 (40.2th percentile) — read the EPSS interpretation.