CVE-2026-110847 n8n before 1.123.83, 2.41.4, and 2.42.1 Stored XSS via Chat Trigger customCss Parameter
Attackers can inject malicious scripts via the Chat Trigger customCss parameter, potentially hijacking sessions of signed-in users on the n8n instance.
- 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
- None listed
What is CVE-2026-110847?
CVE-2026-110847 is a high-severity cross-site scripting vulnerability in n8n-io n8n, published on 14 Oct 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
n8n before 1.123.83, 2.x before 2.41.4, and 2.42.x before 2.42.1 contains a stored cross-site scripting vulnerability in the Chat Trigger hosted-chat page, where insufficiently sanitised customCss values are interpolated into the page as markup. Workflow authors can publish a chat without n8n user authentication whose payload executes on the instance origin, acting on the sessions of signed-in visitors.
Weakness: CWE-79
Which versions are affected by CVE-2026-110847?
How do I fix CVE-2026-110847?
No fix has been published for CVE-2026-110847 yet. Limit exposure of the affected software until one is available.
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-2026-110847 being exploited?
There is no known exploitation of CVE-2026-110847 in the wild and no public exploit code.
Sources
Also known as GHSA-q529-cjvg-c6m6, GHSA-x5cw-hm7v-q7mj.