CVE-2026-65898 | DOMPurify before 3.4.11 fails to clone the ALLOWED_ATTR allo… | CVSS 7.2 HIGH

Description

DOMPurify before 3.4.11 fails to clone the ALLOWED_ATTR allowlist when setConfig() is used with an uponSanitizeAttribute hook, allowing the hook to permanently mutate the shared allowlist. Attackers can register a hook that conditionally allows dangerous attributes like onerror for trusted elements, then submit untrusted content that inherits the polluted allowlist and executes event handlers as stored XSS.

Metadata

CVE ID: CVE-2026-65898
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-07-23 11:03 UTC
Published: 2026-07-23 13:16 UTC
Last updated: 2026-07-23 13:16 UTC
Primary CWE: CWE-79
Improper Neutralization of Input During Web Page Generation …
Vendor / Product: cure53 / DOMPurify
Sources: cve.org · NVD

Severity & Metrics

7.2 HIGH CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Affected products (1)

Vendor	Product	Platform	Versions
cure53	DOMPurify	—	0 < 3.4.11, 3.4.11

Weakness (CWE)

CWE	Source	Description
CWE-79	cna	Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVSS scores (2)

Score	Severity	Version	Source	Vector
7.2	HIGH	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
5.1	MEDIUM	4.0	cna	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

References (2)

GitHub Security Advisory (GHSA-cmwh-pvxp-8882) https://github.com/cure53/DOMPurify/security/advisories/GHSA-cmwh-pvxp-8882
VulnCheck Advisory: DOMPurify before 3.4.11 Permanent Attribute Allowlist Pollution via setConfig https://www.vulncheck.com/advisories/dompurify-before-permanent-attribute-allowlist-pollution-via-setconfig