GitHub Advisoryadvisory · npm

GHSA-rjxq-qqhf-8hwh OpenClaw: MCP Streamable HTTP redirects could forward configured custom headers to another origin

HIGH Published 2026-06-17 Modified 2026-06-17 Official page ↗
Aliases
CVE-2026-53840
Ecosystem
npm
Packages
openclaw
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
Weaknesses
CWE-200
Reviewed
2026-06-17

Affected packages

• npm openclaw: < 2026.5.12 → fixed in 2026.5.12

Description

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.

Related

Alias · CVE (1)

  • CVE-2026-53840 OpenClaw before 2026.5.12 contains an information disclosure vulnerability in streamable-http MCP servers that forwards operator-configured… vulnerability

Weakness · CWE (1)

  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor weakness

References