Trust Boundary Violation in DOMPurify - #VU132354

 

Trust Boundary Violation in DOMPurify - #VU132354

Published: May 27, 2026


Vulnerability identifier: #VU132354
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: N/A
CWE-ID: CWE-501
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: Cure53
Affected software:
DOMPurify

Detailed vulnerability description

The vulnerability allows a remote attacker to bypass sanitization protections and inject disallowed HTML elements or attributes into sanitized output.

The vulnerability exists due to trust boundary violation in DOMPurify hook handling when processing hook callbacks that mutate data.allowedTags or data.allowedAttributes during sanitization with default configuration. A remote attacker can supply crafted content that is sanitized after a hook has widened the default allow-list to bypass sanitization protections and inject disallowed HTML elements or attributes into sanitized output.

User interaction is required to render attacker-influenced content, and the polluted allow-list persists for the lifetime of the DOMPurify instance until a new instance is created.


Remediation

Install security update from vendor's website.

Sources