CVE-2025-59827: Flag Forge is a Capture The Flag (CTF) platform

This month

CRITICAL 9.8REMOTEDOWNGRADE

CVE-2025-59827 is a critical-severity flaw (CVSS 9.8) affecting flagforge. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

Critical severity
Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.4% (top 69%)
CISA exploited list	No
Weakness	CWE-862
Published	2025-09-24
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: flagforge

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2025-09-24 21:15 UTCPublished CVE record published
2026-06-17 09:46 UTCUpdated Record last modified

flagforge flagforge DOWNGRADE

Affected: 2.1.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.1.0

1. Check installed version

apt-cache policy flagforge || rpm -q flagforge || flagforge --version

2. No fixed release: DOWNGRADE to a release before 2.1.0 (Debian / Ubuntu)

apt-cache madison flagforge sudo apt install flagforge=<VERSION_BEFORE_2.1.0> sudo apt-mark hold flagforge

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list flagforge sudo dnf downgrade flagforge-<VERSION_BEFORE_2.1.0> sudo dnf versionlock add flagforge

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2025-59827?

flagforge: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2025-59827 being exploited?

CVE-2025-59827 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2025-59827 affect?

CVE-2025-59827 affects flagforge. Severity is critical (CVSS 9.8). 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 lea

How urgent is CVE-2025-59827?

Priority 47/100. Critical severity; Remotely exploitable, no login, no user action

Related CVEs

CVE-2025-59841 CRITICAL 9.8 UPGRADE Flag Forge is a Capture The Flag (CTF) platform
CVE-2025-59826 HIGH 7.6 DOWNGRADE Flag Forge is a Capture The Flag (CTF) platform
CVE-2025-61777 CRITICAL 9.4 UPGRADE Flag Forge is a Capture The Flag (CTF) platform
CVE-2025-59932 HIGH 8.6 UPGRADE Flag Forge is a Capture The Flag (CTF) platform
CVE-2025-59843 MEDIUM 5.3 UPGRADE Flag Forge is a Capture The Flag (CTF) platform

References

← Back to latest CVEs