GHSA-37gc-85xm-2ww6 CVE-2026-27009

OpenClaw affected by Stored XSS in Control UI via unsanitized assistant name/avatar in inline script injection

Medium npm

Severity: 5.8 / 10; Medium · CVSS 3.1
Exploit chance (EPSS): 0.26%; Chance of exploitation in the next 30 days. Higher than 18.32% of scored vulnerabilities.
Known exploited: No; Not in CISA's catalog
Weakness: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Fix: 2026.2.15; Upgrade openclaw to this version or later

Description

Summary

Stored XSS in the OpenClaw Control UI when rendering assistant identity (name/avatar) into an inline <script> tag without script-context-safe escaping. A crafted value containing </script> could break out of the script tag and execute attacker-controlled JavaScript in the Control UI origin.

Affected Packages / Versions

Package: openclaw (npm)
Affected versions: <= 2026.2.14
Fixed in: >= 2026.2.15 (next release; fix is already merged on main)

Details

The gateway Control UI HTML response previously injected assistantName and assistantAvatar directly into an inline <script> block using JSON.stringify(...). JSON.stringify does not prevent </script> from terminating the script element, enabling stored XSS if an operator/admin sets the assistant identity to a malicious string.

OpenClaw’s Control UI is intended for local use only (see SECURITY.md); this advisory’s CVSS reflects a loopback-only/local-access deployment assumption.

Impact

An attacker with the ability to set assistant identity values (config or agent identity) could cause JavaScript execution for Control UI visitors, enabling token/session theft and privileged actions in the UI.

Fix

Removed inline script injection and serve bootstrap config from a JSON endpoint.
Added a restrictive Content Security Policy for the Control UI (script-src 'self', no inline scripts).

Fix Commit(s)

adc818db4a4b3b8d663e7674ef20436947514e1b
3b4096e02e7e335f99f5986ec1bd566e90b14a7e

Release Process Note

This advisory pre-sets the patched version to the planned next release (2026.2.15). Once that version is published to npm, this advisory can be published without further edits.

Thanks @Adam55A-code for reporting.

Affected versions

npm

Package	Vulnerable	Fixed in
openclaw	`< 2026.2.15`	`2026.2.15`

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

openclaw npm → `2026.2.15`

npm

npm install openclaw@2026.2.15

yarn

yarn add openclaw@2026.2.15

pnpm

pnpm add openclaw@2026.2.15

Severity breakdown

CVSS 3.1 5.8

CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:N

Attack vector: Local
Attack complexity: Low
Privileges required: High
User interaction: Required
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: None

Weakness

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

How to prevent it

Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482]. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
Implementation, Architecture and Design: Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required encoding strategies. For any data that will be output to another web page, especially any data that was received from external inputs, use the appropriate encoding on all non-alphanumeric characters. Parts of the same output document may require different encodings, which will vary depending on whether the output is in the: HTML body Element attributes (such as src="XYZ") URIs JavaScript sections Cascading Style Sheets and style property etc. Note that HTML Entity Encoding is only appropriate for the HTML body. Consult the XSS Prevention Cheat Sheet [REF-724] for more details on the types of encoding and escaping that are needed.
Architecture and Design, Implementation: Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
Architecture and Design: For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
Architecture and Design: If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated.
Implementation: Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8. When an encoding is not specified, a downstream component may choose a different encoding, either by assuming a default encoding or automatically inferring which encoding is being used, which can be erroneous. When the encodings are inconsistent, the downstream component might treat some character or byte sequences as special, even if they are not special in the original encoding. Attackers might then be able to exploit this discrepancy and conduct injection attacks; they even might be able to bypass protection mechanisms that assume the original encoding is also being used by the downstream component. The problem of inconsistent output encodings often arises in web pages. If an encoding is not specified in an HTTP header, web browsers often guess about which encoding is being used. This can open up the browser to subtle XSS attacks.
Implementation: With Struts, write all data from form beans with the bean's filter attribute set to true.
Implementation: To help mitigate XSS attacks against the user's session cookie, set the session cookie to be HttpOnly. In browsers that support the HttpOnly feature (such as more recent versions of Internet Explorer and Firefox), this attribute can prevent the user's session cookie from being accessible to malicious client-side scripts that use document.cookie. This is not a complete solution, since HttpOnly is not supported by all browsers. More importantly, XmlHttpRequest and other powerful browser technologies provide read access to HTTP headers, including the Set-Cookie header in which the HttpOnly flag is set.
Implementation: Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright. When dynamically constructing web pages, use stringent allowlists that limit the character set based on the expected value of the parameter in the request. All input should be validated and cleansed, not just parameters that the user is supposed to specify, but all data in the request, including hidden fields, cookies, headers, the URL itself, and so forth. A common mistake that leads to continuing XSS vulnerabilities is to validate only fields that are expected to be redisplayed by the site. It is common to see data from the request that is reflected by the application server or the application that the development team did not anticipate. Also, a field that is not currently reflected may be used by a future developer. Therefore, validating ALL parts of the HTTP request is recommended. Note that proper output encoding, escaping, and quoting is the most ef
Architecture and Design: When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
Operation: Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].
Operation, Implementation: When using PHP, configure the application so that it does not use register_globals. During implementation, develop the application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.

References

Advisories

nvd.nist.gov/vuln/detail/CVE-2026-27009

Packages

github.com/openclaw/openclaw

Timeline

Feb 18, 2026 Published
Jun 17, 2026 Last updated by the source
Nov 1, 2026 Latest EPSS score

Advisory	Severity	Why it's related
GHSA-3x84-qq85-fj65 OpenClaw: Browser CDP discovery could accept blocked WebSocket URLs	High	Also affects openclaw
GHSA-9c3v-684m-579c OpenClaw MCP SSE redirects could forward Authorization headers	Medium	Also affects openclaw
GHSA-f397-5vjw-v2c2 OpenClaw: Shell inline-command parsing could miss an allowlist check	High	Also affects openclaw
GHSA-rx78-29qr-5hq8 OpenClaw: Workspace-derived service PATH could influence trash command selection	High	Also affects openclaw
GHSA-ccwh-wwpp-6wg5 OpenClaw: Host environment sanitizer missed two Node.js control variables	High	Also affects openclaw
GHSA-985f-72mj-8gf7 OpenClaw: Tool group policy callers could accept unvalidated group IDs	Medium	Also affects openclaw
GHSA-9v8j-9c9g-w66c OpenClaw: Bootstrap token replay could widen pending pairing scopes	Medium	Also affects openclaw
GHSA-c226-q6fx-6j6c OpenClaw: macOS Swift exec allowlist missed combined POSIX inline flags	Medium	Also affects openclaw

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