Vulnerability in Flagforge

CVE-2025-59843

Flag Forge is a Capture The Flag (CTF) platform. From versions 2.0.0 to before 2.3.2, the public endpoint /api/user/[username] returns user email addresses in its JSON response. The fix, intended for release in 2.3.1 but only available starting in version 2.3.2, removes email addresses from public API responses while keeping the endpoint publicly accessible. Users should upgrade to version 2.3.2 or later to eliminate exposure. There are no workarounds for this vulnerability.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (33.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.3% 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-2025-59843: 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-2025-59843?
CVE-2025-59843 is a medium-severity vulnerability in Flagforge, classified under Exposure of Private Personal Information to an Unauthorized Actor. CVSS score: 5.3/10. Published 2025-09-26.
How severe is CVE-2025-59843?
Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2025-59843 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.