CVE-2026-41240
MEDIUM
MEDIUM
Priority: 0.02
BB Relevance:
62/100
Published: 2026-04-23
Modified: 2026-10-26
First seen: 2026-10-29
Status: active
Attack Surface
Network
Low Complexity
No Auth
Integ. Impact
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
Passive
S:
X
AT:
Present
VC:
None
VI:
High
VA:
None
Description
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.
References & Advisories (3)
Product
Release Notes
Patch
Exploit
Mitigation
Patch