CVE-2026-33517
Published: 23 March 2026
Summary
CVE-2026-33517 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Mantisbt Mantisbt. Its CVSS base score is 8.6 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique JavaScript (T1059.007); ranked at the 15.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-14523
Vulnerability details
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…
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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.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
XSS in tag_delete.php directly enables arbitrary JavaScript execution in victim browsers (T1059.007).
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.
Validates web inputs to reject script-related content that could produce XSS.
Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.