SB2026061217 - Security restrictions bypass in DOMPurify

Description

This security bulletin contains information about 1 vulnerability.

1) Protection Mechanism Failure (CVE-ID: N/A)

CWE-ID: CWE-693 - Protection Mechanism Failure

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote user to execute arbitrary script in the context of a Trusted Types sink.

The vulnerability exists due to a protection mechanism failure in the Trusted Types policy handling in DOMPurify when reusing a DOMPurify instance across trust boundaries after calling clearConfig() and requesting RETURN_TRUSTED_TYPE. A remote user can influence a previously supplied trusted types policy on the reused instance to execute arbitrary script in the context of a Trusted Types sink.

Exploitation requires a shared DOMPurify instance, a previously retained unsafe or less-trusted policy, and a later sanitize call that requests RETURN_TRUSTED_TYPE.

Remediation

Install update from vendor's website.

References

• https://github.com/cure53/DOMPurify/security/advisories/GHSA-vxr8-fq34-vvx9
• https://github.com/cure53/DOMPurify