CVE-2026-75838 DOMPurify before 3.4.13 Cross-Site Scripting via IN_PLACE hook
Attackers can execute arbitrary JavaScript via event handlers in detached subtrees bypassing DOMPurify's IN_PLACE sanitization hooks.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-75838?
CVE-2026-75838 is a medium-severity cross-site scripting vulnerability in cure53 DOMPurify, published on 18 Aug 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
DOMPurify before 3.4.13 contains a cross-site scripting vulnerability in IN_PLACE sanitization where element-removal hooks fail to neutralize detached subtrees. Attackers can supply HTML with event handlers on descendant elements that execute after sanitization completes, even though the returned root appears clean.
Weakness: CWE-79
Which versions are affected by CVE-2026-75838?
2 open source packages ship an affected version, including dompurify.
| Package | Affected | Fixed in |
|---|---|---|
dompurify npm | All versions | 3.4.13 |
dompurify npm | All versions | 3.4.13 |
Linux distribution packages (2)
grafana12.4 Red Hat:hummingbird:1 | All versions | 0:12.4.10-0.7.hum1 |
grafana13.2 Red Hat:hummingbird:1 | All versions | 0:13.2.1-0.6.hum1 |
How do I fix CVE-2026-75838?
Upgrade dompurify to 3.4.13 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-2026-75838 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-75838 exists.
Sources
Also known as CLEANSTART-2026-NP83776, CLSA-2026-1789146579, CLSA-2026-1789146735, CLSA-2026-1789155227, CLSA-2026-1792497323, CLSA-2026-1792509522 and 26 more.