Vulnerability Description
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 Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Cure53 | Dompurify | >= 3.0.0, < 3.4.9 |
Related Weaknesses (CWE)
References
- https://github.com/cure53/DOMPurify/commit/825e617753ac1169306a542d3174a77f717a0Patch
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-vxr8-fq34-vvx9ExploitThird Party Advisory
- https://www.vulncheck.com/advisories/dompurify-before-trusted-types-policy-stateThird Party Advisory
FAQ
What is CVE-2026-65899?
CVE-2026-65899 is a vulnerability with a CVSS score of 6.1 (MEDIUM). 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 ...
How severe is CVE-2026-65899?
CVE-2026-65899 has been rated MEDIUM with a CVSS base score of 6.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-65899?
Check the references section above for vendor advisories and patch information. Affected products include: Cure53 Dompurify.