CVE-2025-59841
Published: 25 September 2025
Summary
CVE-2025-59841 is a critical-severity Session Fixation (CWE-384) vulnerability in Flagforge Flagforge. Its CVSS base score is 9.8 (Critical).
Operationally, ranked at the 25.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-31126
Vulnerability details
Flag Forge is a Capture The Flag (CTF) platform. In versions from 2.2.0 to before 2.3.1, the FlagForge web application improperly handles session invalidation. Authenticated users can continue to access protected endpoints, such as /api/profile, even after logging out. CSRF…
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tokens are also still valid post-logout, which can allow unauthorized actions. This issue has been patched in version 2.3.1.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Automatically terminating sessions after a defined period directly enforces session expiration, preventing indefinite session lifetimes that attackers can exploit.
Re-authentication after inactivity or time-based triggers prevents indefinite use of potentially hijacked or stale sessions.
Locks the device (typically after inactivity) until re-authentication, addressing insufficient session expiration by preventing indefinite access.
Terminating sessions and network connections upon completion prevents insufficient session expiration.
Directly enforces termination of network sessions after inactivity or end-of-session, preventing indefinite session lifetime.
Enforces proper session ID generation and binding, preventing fixation of a known session token.
Consistent clocks across systems allow session expiration and timeout enforcement to function as intended in distributed environments.
When the non-persistent artifact is a session or connection, mandatory termination implements the missing expiration that CWE-613 describes.