CVE-2026-41240

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.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
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

Configurations

Configuration 1 (hide)

cpe:2.3:a:cure53:dompurify:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-23 16:16

Updated : 2026-06-17 10:46

NVD link : CVE-2026-41240

Mitre link : CVE-2026-41240

CVE.ORG link : CVE-2026-41240

JSON object : View

Products Affected

cure53

dompurify

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-183

Permissive List of Allowed Inputs

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