CVE-2026-53840 is a high-severity security vulnerability in openclaw (npm), affecting versions < 2026.5.12. It is fixed in 2026.5.12.
Summary OpenClaw supports remote MCP Streamable HTTP servers with operator-configured custom headers. In affected releases, those headers could be forwarded when the MCP endpoint responded with a cross-origin redirect. This issue is limited to configured MCP Streamable HTTP servers that use custom headers. It does not expose unrelated OpenClaw credentials. Affected configurations This affects deployments where an MCP server is configured with: transportType: "streamable-http" sensitive custom headers under mcp.servers.*.headers an MCP endpoint that is malicious, compromised, or able to redirect to another origin Impact Custom MCP headers, such as API keys or tenant-routing headers, could be sent to the redirect target. The exposed credential scope depends on the header the operator configured for that MCP server. Patched Versions The first stable patched version is 2026.5.12. Mitigations Upgrade to [email protected] or later. Before upgrading, avoid custom MCP headers with servers you do not fully trust, and rotate any MCP-specific credentials that may have been exposed by a redirecting endpoint.
CVE-2026-53840 has a CVSS score of 7.1 (High). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.
A fixed version is available (2026.5.12). Upgrading removes the vulnerable code path.
npm
openclaw (< 2026.5.12)openclaw → 2026.5.12 (npm)Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.
Kodem's runtime-powered SCA identifies whether CVE-2026-53840 is reachable in your applications. Explore open-source security for your team.
See if CVE-2026-53840 is reachable in your applications. Get a demo
Upgrade openclaw to 2026.5.12 or later to resolve this vulnerability.
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
CVE-2026-53840 is a high-severity security vulnerability in openclaw (npm), affecting versions < 2026.5.12. It is fixed in 2026.5.12.
CVE-2026-53840 has a CVSS score of 7.1 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
openclaw (npm) versions < 2026.5.12 is affected.
Yes. CVE-2026-53840 is fixed in 2026.5.12. Upgrade to this version or later.
Whether CVE-2026-53840 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
Upgrade openclaw to 2026.5.12 or later.