Vulnerability-Lookup

GHSA-J535-V25Q-VX3Q

Vulnerability from github – Published: 2026-09-10 15:12 – Updated: 2026-09-10 15:12

Summary

n8n: Regular Expression Denial of Service in the Default Blocked-File-Pattern Match via a Git Node Clone Path

Details

Impact

The 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.

Patches

The 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.

Workarounds

If upgrading is not immediately possible, administrators should consider the following temporary mitigations: - Restrict n8n instance access to fully trusted users only. - Disable the Git node by adding n8n-nodes-base.git to the NODES_EXCLUDE environment variable. - Set N8N_BLOCK_FILE_PATTERNS to a backtracking-safe equivalent pattern to replace the vulnerable default.

These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

Severity

7.1 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "n8n"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.123.76"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "n8n"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.38.0"
            },
            {
              "fixed": "2.38.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "n8n"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.0.0"
            },
            {
              "fixed": "2.37.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-86081"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-10T15:12:00Z",
    "nvd_published_at": "2026-09-08T22:19:17Z",
    "severity": "HIGH"
  },
  "details": "## Impact\n\nThe Git node\u0027s 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.",
  "id": "GHSA-j535-v25q-vx3q",
  "modified": "2026-09-10T15:12:00Z",
  "published": "2026-09-10T15:12:00Z",
  "references": [
    {
      "type": "WEB",
      "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"
    },
    {
      "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"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "n8n: Regular Expression Denial of Service in the Default Blocked-File-Pattern Match via a Git Node Clone Path"
}

CVE-2026-86081 (GCVE-0-2026-86081)

Vulnerability from cvelistv5 – Published: 2026-09-08 21:24 – Updated: 2026-09-09 13:45

Title

n8n: Regular Expression Denial of Service in the Default Blocked-File-Pattern Match via a Git Node Clone Path

Summary

n8n is an open source workflow automation platform. Prior to 1.123.76, 2.37.7, and 2.38.2, the Git node clone operation matched an attacker-controlled destination path against the default N8N_BLOCK_FILE_PATTERNS regular expression. The pattern ^(./).git(/.)$ allowed catastrophic backtracking and ran synchronously in the main n8n process. An authenticated workflow editor could therefore freeze the instance with one workflow execution; the affected default is declared in packages/@n8n/config/src/configs/security.config.ts. This issue is fixed in versions 1.123.76, 2.37.7 and 2.38.2.

Severity

7.1 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-09 13:45 UTC

CWE

CWE-1333 - Inefficient Regular Expression Complexity

Assigner

GitHub_M mitre root

References

4 references

URL	Tags
https://github.com/n8n-io/n8n/security/advisories…	x_refsource_CONFIRM
https://github.com/n8n-io/n8n/releases/tag/n8n@1.123.76	x_refsource_MISC
https://github.com/n8n-io/n8n/releases/tag/n8n@2.37.7	x_refsource_MISC
https://github.com/n8n-io/n8n/releases/tag/n8n@2.38.2	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
n8n-io	n8n	Affected: >= 2.38.0, < 2.38.2 Affected: >= 2.0.0, < 2.37.7 Affected: < 1.123.76

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JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-86081",
                "options": [
                  {
                    "Exploitation": "none"
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                  },
                  {
                    "Technical Impact": "partial"
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                "role": "CISA Coordinator",
                "timestamp": "2026-09-09T13:45:20.437735Z",
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          "versions": [
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      "descriptions": [
        {
          "lang": "en",
          "value": "n8n is an open source workflow automation platform. Prior to 1.123.76, 2.37.7, and 2.38.2, the Git node clone operation matched an attacker-controlled destination path against the default N8N_BLOCK_FILE_PATTERNS regular expression. The pattern ^(./).git(/.)$ allowed catastrophic backtracking and ran synchronously in the main n8n process. An authenticated workflow editor could therefore freeze the instance with one workflow execution; the affected default is declared in packages/@n8n/config/src/configs/security.config.ts. This issue is fixed in versions 1.123.76, 2.37.7 and 2.38.2."
        }
      ],
      "metrics": [
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      "providerMetadata": {
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.