CVE-2026-65902

DOMPurify before 3.4.7 (affected versions <= 3.4.5) passes direct references to the module-level DEFAULT_ALLOWED_TAGS and DEFAULT_ALLOWED_ATTR sets to the uponSanitizeElement and uponSanitizeAttribute hooks via data.allowedTags / data.allowedAttributes when sanitize is called without an explicit cfg.ALLOWED_TAGS / cfg.ALLOWED_ATTR array. A hook that mutates these fields permanently widens the default allow-lists for the lifetime of the DOMPurify instance, so all subsequent default-config sanitize calls inherit the widened defaults and attacker payloads using the poisoned tag/attribute name survive sanitization. removeAllHooks(), clearConfig(), and passing a fresh cfg do not recover the state; only constructing a new DOMPurify instance does.

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/7996f1dc78eb8b7922388aed75d94a9f8fad9a36	Patch
https://github.com/cure53/DOMPurify/security/advisories/GHSA-76mc-f452-cxcm	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/dompurify-before-hook-mutation-pollution-via-allowedtags	Third Party Advisory
https://github.com/cure53/DOMPurify/security/advisories/GHSA-76mc-f452-cxcm	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-07-23 14:18

Updated : 2026-07-28 15:51

NVD link : CVE-2026-65902

Mitre link : CVE-2026-65902

CVE.ORG link : CVE-2026-65902

JSON object : View

Products Affected

cure53

dompurify

CWE

CWE-501

Trust Boundary Violation

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