CVE-2026-65912 DOMPurify before 3.3.2 URI Validation Bypass via ADD_ATTR
Attackers can bypass URI validation in DOMPurify using specific predicate functions to inject JavaScript, leading to DOM-based XSS.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-65912?
CVE-2026-65912 is a medium-severity cross-site scripting vulnerability in cure53 DOMPurify, published on 23 Jul 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
DOMPurify before 3.3.2 contains a URI validation bypass vulnerability when ADD_ATTR is provided as a predicate function via EXTRA_ELEMENT_HANDLING.attributeCheck. Attackers can supply a predicate that accepts specific attribute and tag combinations to bypass URI-safe validation, allowing unsafe protocols like javascript: to survive sanitization and execute as DOM-based XSS when the link is activated.
Weakness: CWE-79
Which versions are affected by CVE-2026-65912?
2 open source packages ship an affected version, including dompurify. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
dompurify npm | All versions | 3.3.2 |
dompurify npm | All versions | 3.3.2 |
Products include Cure53 Dompurify.
How do I fix CVE-2026-65912?
Upgrade dompurify to 3.3.2 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-65912 being exploited?
There is no known exploitation of CVE-2026-65912 in the wild and no public exploit code.
Other vulnerabilities in cure53 DOMPurify
- CVE-2024-47875 DOMPurify nesting-based mXSS
- CVE-2024-48910 DOMPurify vulnerable to tampering by prototype polution
- CVE-2026-47423 DOMPurify XSS via `selectedcontent` re-clone
- CVE-2024-45801 Tampering by prototype polution in DOMPurify
- CVE-2026-49978 DOMPurify IN_PLACE Sanitization Bypass via Attached Shadow Root Inside <template>.content
Sources
Also known as CLEANSTART-2026-BC33249, CLSA-2026-1784769607, CLSA-2026-1784856415, DEBIAN-CVE-2026-65912, ECHO-6f5f-72eb-f9a6, GHSA-cjmm-f4jc-qw8r and 12 more.