What’s Vulnerable › Vulnerabilities

CVE-2026-33517: MantisBT Vulnerable to Stored HTML Injection in Tag Delete Confirmation

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-03-23 · updated 2026-06-17
• Weakness: CWE-79

Description

Mantis Bug Tracker (MantisBT) is an open source issue tracker. In version 2.28.0, when deleting a Tag (tag_delete.php), improper escaping of its name when displaying the confirmation message allows an attacker to inject HTML and, if CSP settings permit, achieve execution of arbitrary JavaScript. Version 2.28.1 fixes the issue. Workarounds include reverting commit d6890320752ecf37bd74d11fe14fe7dc12335be9 and/or manually editing language files to remove the sprintf placeholder `%1$s` from `$s_tag_delete_message` string.

Affected products

• mantisbt: 2.28.0

References

• https://github.com/mantisbt/mantisbt/commit/80990f43153167c73f11eb4b2bc7108d0c3d6b46
• https://github.com/mantisbt/mantisbt/commit/d6890320752ecf37bd74d11fe14fe7dc12335be9
• https://github.com/mantisbt/mantisbt/security/advisories/GHSA-fh48-f69w-7vmp

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