Critical severity · published Sep 25, 2025
CVE-2025-59841
FlagForgeCTF's Improper Session Handling Allows Access After Logout
9.8
CVSS
0.4%
EPSS
No
On KEV
Description
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 tokens are also still valid post-logout, which can allow unauthorized actions. This issue has been patched in version 2.3.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FL
flagForge · FlagForgeCTF
>= 2.2.0, < 2.3.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-59841
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-59841
Patch
https://github.com/FlagForgeCTF/flagForge/commit/304b6c82a4f76871b336404b91e5cdd8a7d7d5bd
Vendor Advisory
https://github.com/FlagForgeCTF/flagForge/security/advisories/GHSA-h6pr-4cwv-6cjg
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