CVE-2026-66421

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 classification

• disclosure@vulncheck.com: CWE-79

Primary references

• disclosure@vulncheck.com — Exploit, Mitigation, Third Party Advisory
• disclosure@vulncheck.com — Product
• disclosure@vulncheck.com — Exploit, Third Party Advisory
• 134c704f-9b21-4f2e-91b3-4a467353bcc0 — Exploit, Mitigation, Third Party Advisory