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

24 Oct 2026, 13:10

Type	Values Removed	Values Added
Summary		(es) DOMPurify anterior a la versión 3.4.0 contiene un error lógico en la función ADD_TAGS donde la evaluación de cortocircuito permite que las etiquetas prohibidas eludan las restricciones de FORBID_TAGS. Los atacantes pueden elaborar una entrada que contenga etiquetas listadas en FORBID_TAGS que también se añaden a través de la función ADD_TAGS, provocando que se retengan en la salida saneada.

Information

Published : 2026-07-23 14:18

Updated : 2026-10-24 13:10

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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