How severe is CVE-2025-59841?

CVE-2025-59841 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-59841 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-59841?

CVE-2025-59841 affects Flagforge. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-59841?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-59841 have an EU (EUVD) identifier?

Yes. CVE-2025-59841 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-31126.

When was CVE-2025-59841 published?

CVE-2025-59841 was published on 2025-09-25 and last updated on 2026-06-17.

CVE-2025-59841

CVE-2025-59841 is a critical-severity vulnerability in Flagforge with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-384.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-31126
Weakness: CWE-384
Affected product: Flagforge
Published: 2025-09-25
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2025-59841?: 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.
How severe is CVE-2025-59841?: CVE-2025-59841 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-59841 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-59841?: CVE-2025-59841 affects Flagforge. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-59841?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-59841 have an EU (EUVD) identifier?: Yes. CVE-2025-59841 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-31126.
When was CVE-2025-59841 published?: CVE-2025-59841 was published on 2025-09-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:flagforge:flagforge:*:*:*:*:*:*:*:*

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