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...

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.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

0.34%

26.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-770

Affected Software

Vendor	Product	Versions
Mantisbt	Mantisbt	< 2.27.2

References

Timeline

Published: Nov 4, 2025
Last Modified: Jun 17, 2026
Status: Analyzed

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.

How severe is CVE-2025-46556?

CVE-2025-46556 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.34% probability of exploitation in the next 30 days.

How do I fix CVE-2025-46556?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.