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Vulnerability record · CVE-2025-59841 · published 25 September 2025

CVE-2025-59841: Flagforge insufficient session expiration vulnerability

Flagforge · Flagforge

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.

9.8 CVSS 3.1 Critical EPSS 0.42% · top 65.9% CWE-384 · CWE-384CWE-613 · Insufficient session expiration
9.8CVSS 3.1 base score
0.42%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/FlagForgeCTF/flagForge/commit/304b6c82a4f76871b336404b91e5cdd8a7d7d5bd Patch
https://github.com/FlagForgeCTF/flagForge/security/advisories/GHSA-h6pr-4cwv-6cjg Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2025-59841), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.