CVE-2026-66421 OpenClaw Dashboard Stored XSS via lastMessage Session Field
Unauthenticated attackers can inject malicious scripts into session transcripts, leading to admin session hijacking and unauthorized modification of agent instructions.
- 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
- None listed
What is CVE-2026-66421?
CVE-2026-66421 is a high-severity cross-site scripting vulnerability in tugcantopaloglu openclaw-dashboard, published on 30 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
OpenClaw Dashboard contains a stored cross-site scripting vulnerability that allows unauthenticated remote attackers to execute arbitrary JavaScript in the administrator's browser session by injecting HTML markup into agent transcript messages processed through the sessions API. Attackers can craft a message containing inline event handler payloads such as an img tag with an onerror attribute within the 60-character rendering budget, which is stored in the session transcript and interpolated unsanitized into innerHTML on the default landing page, allowing theft of session tokens and unauthorized calls to authenticated administrative endpoints including agent instruction file modification.
Weakness: CWE-79
Which versions are affected by CVE-2026-66421?
It affects 1 product.
Products include Tugcantopaloglu Openclaw Agent Dashboard.
How do I fix CVE-2026-66421?
No fix has been published for CVE-2026-66421 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-2026-66421 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-66421 exists.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in tugcantopaloglu openclaw-dashboard
Sources
Also known as GHSA-hc44-65x2-rvc2.