9.3
CRITICAL CVSS 3.1
CVE-2026-66421
OpenClaw Dashboard Stored XSS via lastMessage Session Field
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.

INFO

Published Date :

July 30, 2026, 11:16 p.m.

Last Modified :

July 30, 2026, 11:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-66421 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 CRITICAL [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Sanitize user input for HTML markup to prevent stored XSS.
  • Sanitize HTML markup in agent transcript messages.
  • Avoid interpolating unsanitized data into innerHTML.
  • Validate and restrict input character limits.
  • Update OpenClaw Dashboard to the latest version.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-66421 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-66421 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-66421 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-66421 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 30, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'tugcantopaloglu', 'product': 'openclaw-dashboard', 'versions': [{'status': 'affected', 'version': '1.1.0', 'versionType': 'custom'}], 'defaultStatus': 'affected'}]
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
    Added CWE CWE-79
    Added Reference https://github.com/theopaid/Stored-Cross-Site-Scripting-Via-Agent-Messages-Leading-To-Session-Token-Theft-openclaw-dashboard-
    Added Reference https://github.com/tugcantopaloglu/openclaw-dashboard
    Added Reference https://www.vulncheck.com/advisories/openclaw-dashboard-stored-xss-via-lastmessage-session-field
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.