CVE-2025-46556: mantisbt DoS — Fix

Description

Mantis Bug Tracker (MantisBT) is an open source issue tracker. Versions 2.27.1 and below allow attackers to permanently corrupt issue activity logs by submitting extremely long notes (tested with 4,788,761 characters) due to a lack of server-side validation of note length. Once such a note is added, the activity stream UI fails to render; therefore, new notes cannot be displayed, effectively breaking all future collaboration on the issue. This issue is fixed in version 2.27.2.

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CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-770 CWE-770

Affected Products

Vendor	Product	Versions
mantisbt	mantisbt	< 2.27.2

References

Advisories & Patches

https://github.com/mantisbt/mantisbt/commit/c99a41272532ba49b5c8dccb7797afead9864234 https://github.com/mantisbt/mantisbt/commit/d5cec6bffb44d54bd412c186b9baa409b1aa4238 https://github.com/mantisbt/mantisbt/commit/e9119c68b4a0eaa0bbde3deb121e81f5f7157361 https://github.com/mantisbt/mantisbt/security/advisories/GHSA-r3jf-hm7q-qfw5

Frequently Asked Questions

What is CVE-2025-46556? +

Mantis Bug Tracker (MantisBT) is an open source issue tracker. Versions 2.27.1 and below allow attackers to permanently corrupt issue activity logs by submitting extremely long notes (tested with 4,788,761 characters) due to a lack of server-side validation of note length. Once such a note is added, the activity stream UI fails to render; therefore, new notes cannot be displayed, effectively breaking all future collaboration on the issue. This issue is fixed in version 2.27.2. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2025-46556? +

CVE-2025-46556 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-46556? +

CVE-2025-46556 affects products from mantisbt, specifically: mantisbt. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-46556? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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