CVE-2026-65899

DOMPurify 3.0.0 before 3.4.9 does not reset the retained Trusted Types policy when clearConfig() is called, so a DOMPurify instance reused across trust boundaries stays bound to a previously supplied TRUSTED_TYPES_POLICY. A later caller that requests RETURN_TRUSTED_TYPE output receives a TrustedHTML object created by the old (potentially unsafe) policy rather than a clean default, which can lead to script execution at a Trusted Types sink. Passing TRUSTED_TYPES_POLICY: null on the later call also does not clear the retained policy.

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/825e617753ac1169306a542d3174a77f717a0cf6	Patch
https://github.com/cure53/DOMPurify/security/advisories/GHSA-vxr8-fq34-vvx9	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/dompurify-before-trusted-types-policy-state-contamination	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 15:53

NVD link : CVE-2026-65899

Mitre link : CVE-2026-65899

CVE.ORG link : CVE-2026-65899

JSON object : View

Products Affected

cure53

dompurify

CWE

CWE-693

Protection Mechanism Failure

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