CVE-2026-109345 DOMPurify before 3.4.16 XSS via IN_PLACE Returned Rawtext Root
Attackers can bypass sanitization in DOMPurify's IN_PLACE mode to execute arbitrary scripts via crafted style elements, affecting applications using this library.
- 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-2026-109345?
CVE-2026-109345 is a medium-severity cross-site scripting vulnerability in cure53 DOMPurify, published on 12 Oct 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 3.4.16 contains a cross-site scripting vulnerability that allows attackers to bypass sanitization because IN_PLACE mode returns a force-removed style element whose text content still carries markup. Attackers can supply a style element containing a closing style tag and an img onerror payload, which executes script when the application serializes and re-parses the returned node.
Weakness: CWE-79
Which versions are affected by CVE-2026-109345?
2 open source packages ship an affected version, including dompurify.
| Package | Affected | Fixed in |
|---|---|---|
dompurify npm | All versions | 3.4.16 |
dompurify npm | All versions | 3.4.16 |
How do I fix CVE-2026-109345?
Upgrade dompurify to 3.4.16 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-2026-109345 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109345 exists.
Sources
Also known as CLSA-2026-1791626851, CLSA-2026-1791626965, CLSA-2026-1791627235, CLSA-2026-1791627414, CLSA-2026-1791627570, CLSA-2026-1791627799 and 40 more.