---
id: CVE-2025-59841
title: Flag Forge is a Capture The Flag (CTF) platform
summary: >-
  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/…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-384
  - CWE-613
vendor: flagforge
product: flagforge
affected:
  - 'flagforge >= 2.2, < 2.3.1'
patched:
  - flagforge 2.3.1
published: '2025-09-25'
updated: '2026-10-11'
sourceUpdated: '2026-10-11T20:10:00.200'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-59841'
references:
  - url: >-
      https://github.com/FlagForgeCTF/flagForge/commit/304b6c82a4f76871b336404b91e5cdd8a7d7d5bd
    label: security-advisories@github.com
  - url: >-
      https://github.com/FlagForgeCTF/flagForge/security/advisories/GHSA-h6pr-4cwv-6cjg
    label: security-advisories@github.com
tags:
  - nvd
epss: 0.00423
epssPercentile: 0.34705
ingestedAt: '2026-10-12T14:50:33.995Z'
---

## Overview

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.

## Affected

- `flagforge >= 2.2, < 2.3.1`

## Remediation

Upgrade past the affected range:

- `flagforge 2.3.1`