CVE-2026-65911

In DOMPurify through 3.3.3, function predicates supplied via ADD_ATTR or ADD_TAGS to DOMPurify.sanitize() persist in internal state (EXTRA_ELEMENT_HANDLING) across subsequent sanitize() calls on the same instance. If a later call on the same instance provides ADD_ATTR or ADD_TAGS as an array rather than a function, the previously set function handler is neither cleared nor overwritten, so it continues to approve attacker-controlled attributes or tags. This can allow dangerous event-handler attributes or forbidden tags (bypassing FORBID_TAGS) to survive sanitization, resulting in cross-site scripting. The vendor (Cure53) considers this an edge case outside DOMPurify's threat model; the referenced advisory lists 3.4.0 as the patched version.

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-9p3w-6h5p-cv75	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/dompurify-before-xss-via-add-attr-add-tags-state-leakage	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 15:50

NVD link : CVE-2026-65911

Mitre link : CVE-2026-65911

CVE.ORG link : CVE-2026-65911

JSON object : View

Products Affected

cure53

dompurify

CWE

CWE-79

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

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