{"schema":"threatline.record/2","record":{"id":"GHSA-728h-pmr2-7cgh","aliases":["GHSA-728h-pmr2-7cgh"],"summary":"Send-and-Wait HMAC Bypass Allows Unauthenticated Approval of Waiting Executions","details":"## Impact\n\nThe waiting-webhook endpoint accepts a Send-and-Wait node reference in two forms. It decided which validation to apply before normalising the second form, so a request in that shape was accepted without the signature approvals require. A caller holding an execution's resume token can release an approval intended for someone else; everything downstream then runs under the workflow owner's credentials, which depending on the workflow can reach command execution.\n\n## Patches\n\nThe issue has been fixed in n8n versions 2.42.1 and 2.41.4. Users should upgrade to one of these versions or later to remediate the vulnerability.\n\n## Workarounds\n\nIf upgrading is not immediately possible, administrators should consider the following temporary mitigations:\n- Restrict n8n instance access to fully trusted users only.\n- Avoid using Send-and-Wait nodes that gate high-consequence actions in workflows where an earlier public, unauthenticated trigger node exposes a `resumeToken` to external callers.\n- Restrict or disable public webhook and chat trigger endpoints that precede Send-and-Wait approval nodes until the instance is patched.\n\nThese workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.","categories":["Frameworks"],"product":"n8n","vendor":"","ecosystem":null,"affected_ranges":[{"source":"GitHub Advisory Database","source_url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-728h-pmr2-7cgh","source_modified_at":"2026-09-30T08:35:24Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"n8n"},"range":"< 2.42.1"},{"source":"GitHub Advisory Database","source_url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-728h-pmr2-7cgh","source_modified_at":"2026-09-30T08:35:24Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"n8n"},"range":"< 2.41.4"}],"fixed_versions":[],"cvss":7,"severity":"High","kev":{"listed":false},"epss":{"probability":null,"percentile":null,"score_date":null},"published_at":"2026-09-30T08:35:24Z","modified_at":"2026-09-30T08:35:24Z","provenance":[{"source":"GitHub Advisory Database","url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-728h-pmr2-7cgh","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-09-30T08:35:24Z"}],"sources":["GitHub Advisory Database"],"references":[],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-09-30T08:35:24Z","content_hash":"d79d6b6465b19627a93cf5c3679b819aa130480790675c099b994a759a2715ed"}}