{"id":"GHSA-rjxq-qqhf-8hwh","summary":"OpenClaw: MCP Streamable HTTP redirects could forward configured custom headers to another origin","details":"### Summary\n\nOpenClaw 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.\n\nThis issue is limited to configured MCP Streamable HTTP servers that use custom headers. It does not expose unrelated OpenClaw credentials.\n\n### Affected configurations\n\nThis affects deployments where an MCP server is configured with:\n\n- `transportType: \"streamable-http\"`\n- sensitive custom headers under `mcp.servers.*.headers`\n- an MCP endpoint that is malicious, compromised, or able to redirect to another origin\n\n### Impact\n\nCustom 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.\n\n### Patched Versions\n\nThe first stable patched version is `2026.5.12`.\n\n### Mitigations\n\nUpgrade to `openclaw@2026.5.8` 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.","aliases":["CVE-2026-53840"],"modified":"2026-06-17T18:11:28.897834Z","published":"2026-06-17T17:55:06Z","database_specific":{"nvd_published_at":null,"cwe_ids":["CWE-200"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2026-06-17T17:55:06Z"},"references":[{"type":"WEB","url":"https://github.com/openclaw/openclaw/security/advisories/GHSA-rjxq-qqhf-8hwh"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53840"},{"type":"PACKAGE","url":"https://github.com/openclaw/openclaw"},{"type":"WEB","url":"https://www.vulncheck.com/advisories/openclaw-custom-header-leakage-via-mcp-streamable-http-cross-origin-redirects"}],"affected":[{"package":{"name":"openclaw","ecosystem":"npm","purl":"pkg:npm/openclaw"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2026.5.12"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-rjxq-qqhf-8hwh/GHSA-rjxq-qqhf-8hwh.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N"}]}