DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Versions prior to 3.4.0 have an inconsistency between FORBID_TAGS and FORBID_ATTR handling when function-based ADD_TAGS is used. Commit c361baa added an early exit for FORBID_ATTR at line 1214. The same fix was not applied to FORBID_TAGS. At line 1118-1123, when EXTRA_ELEMENT_HANDLING.tagCheck returns true, the short-circuit evaluation skips the FORBID_TAGS check entirely. This allows forbidden elements to survive sanitization with their attributes intact. Version 3.4.0 patches the issue.
Fix
Patch, vendor advisory and mitigation references on NVD 3
- https://github.com/cure53/DOMPurify/commit/c361baa18dbdcb3344a41110f4c48ad85bf48f80 Patch
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-h7mw-gpvr-xq4m Exploit, Mitigation, Patch, Vendor Advisory
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-h7mw-gpvr-xq4m Exploit, Mitigation, Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 6.0 · cure53NVD modified 2026-10-26 21:10
Affected (CPE criteria) 1
cpe:2.3:a:cure53:dompurify:*:*:*:*:*:*:*:*
References 4
- https://github.com/cure53/DOMPurify/commit/c361baa18dbdcb3344a41110f4c48ad85bf48f80 Patch
- https://github.com/cure53/DOMPurify/releases/tag/3.4.0 Product, Release Notes
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-h7mw-gpvr-xq4m Exploit, Mitigation, Patch, Vendor Advisory
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-h7mw-gpvr-xq4m Exploit, Mitigation, Patch, Vendor Advisory