{"id":"CVE-2026-86081","aliases":["GHSA-j535-v25q-vx3q"],"url":"https://o3.security/vulnerability/CVE-2026-86081","summary":"n8n: Regular Expression Denial of Service in the Default Blocked-File-Pattern Match via a Git Node Clone Path","details":"## Impact\n\nThe Git node's clone operation matched the destination path against the default `N8N_BLOCK_FILE_PATTERNS` expression, which was written so that a crafted path caused catastrophic backtracking. Evaluation runs synchronously in the main n8n process, so an authenticated user could freeze the instance for everyone with a single workflow execution and no unusual configuration. The patch rewrites the pattern so that matching is linear in the length of the path.\n\n## Patches\n\nThe issue has been fixed in n8n versions 1.123.76, 2.37.7, and 2.38.2. 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- Disable the Git node by adding `n8n-nodes-base.git` to the `NODES_EXCLUDE` environment variable.\n- Set `N8N_BLOCK_FILE_PATTERNS` to a backtracking-safe equivalent pattern to replace the vulnerable default.\n\nThese workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.","published":"2026-09-08T21:24:20.936Z","modified":"2026-10-21T03:00:31.950555289Z","cvss":null,"epss":{"score":0.00322,"percentile":0.25295,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"n8n","fixedVersion":"1.123.76"},{"ecosystem":"npm","name":"n8n","fixedVersion":"2.38.2"},{"ecosystem":"npm","name":"n8n","fixedVersion":"2.37.7"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/n8n-io/n8n/releases/tag/n8n@1.123.76"},{"type":"WEB","url":"https://github.com/n8n-io/n8n/releases/tag/n8n@2.37.7"},{"type":"WEB","url":"https://github.com/n8n-io/n8n/releases/tag/n8n@2.38.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86081.json"},{"type":"ADVISORY","url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-j535-v25q-vx3q"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86081"},{"type":"PACKAGE","url":"https://github.com/n8n-io/n8n"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T03:00:31.950555289Z"}}