Auth bypass in Flagforge

CVE-2025-59827

Flag Forge is a Capture The Flag (CTF) platform. In version 2.1.0, the /api/admin/assign-badge endpoint lacks proper access control, allowing any authenticated user to assign high-privilege badges (e.g., Staff) to themselves. This could lead to privilege escalation and impersonation of administrative roles. This issue has been patched in version 2.2.0.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (28.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 29th percentile — 28.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-59827: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-59827?
CVE-2025-59827 is a critical-severity vulnerability in Flagforge, classified under Missing Authorization. CVSS score: 9.8/10. Published 2025-09-24.
How severe is CVE-2025-59827?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2025-59827 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.