CVE-2026-65903

DOMPurify before 3.4.0 contains a logic error in the ADD_TAGS function where short-circuit evaluation allows forbidden tags to bypass FORBID_TAGS restrictions. Attackers can craft input containing tags listed in FORBID_TAGS that are also added via ADD_TAGS function, causing them to be retained in sanitized output.

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/security/advisories/GHSA-39q2-94rc-95cp	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/dompurify-before-add-tags-function-bypasses-forbid-tags	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

28 Jul 2026, 15:51

Type	Values Removed	Values Added
CPE		cpe:2.3:a:cure53:dompurify::::::::
First Time		Cure53 dompurify Cure53
References	~~() https://github.com/cure53/DOMPurify/security/advisories/GHSA-39q2-94rc-95cp -~~	() https://github.com/cure53/DOMPurify/security/advisories/GHSA-39q2-94rc-95cp - Exploit, Third Party Advisory
References	~~() https://www.vulncheck.com/advisories/dompurify-before-add-tags-function-bypasses-forbid-tags -~~	() https://www.vulncheck.com/advisories/dompurify-before-add-tags-function-bypasses-forbid-tags - Third Party Advisory

23 Jul 2026, 14:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-23 14:18

Updated : 2026-07-28 15:51

NVD link : CVE-2026-65903

Mitre link : CVE-2026-65903

CVE.ORG link : CVE-2026-65903

JSON object : View

Products Affected

cure53

dompurify

CWE

CWE-697

Incorrect Comparison

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