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GHSA-RQ6Q-WR2Q-7PGP

Vulnerability from github – Published: 2026-01-21 22:36 – Updated: 2026-01-22 15:41
VLAI
Summary
Backstage has a Possible Symlink Path Traversal in Scaffolder Actions
Details

Impact

Multiple Scaffolder actions and archive extraction utilities were vulnerable to symlink-based path traversal attacks. An attacker with access to create and execute Scaffolder templates could exploit symlinks to:

  1. Read arbitrary files via the debug:log action by creating a symlink pointing to sensitive files (e.g., /etc/passwd, configuration files, secrets)
  2. Delete arbitrary files via the fs:delete action by creating symlinks pointing outside the workspace
  3. Write files outside the workspace via archive extraction (tar/zip) containing malicious symlinks

This affects any Backstage deployment where users can create or execute Scaffolder templates.

Patches

This vulnerability is fixed in the following package versions:

  • @backstage/backend-defaults version 0.12.2, 0.13.2, 0.14.1, 0.15.0
  • @backstage/plugin-scaffolder-backend version 2.2.2, 3.0.2, 3.1.1
  • @backstage/plugin-scaffolder-node version 0.11.2, 0.12.3

Users should upgrade to these versions or later.

Workarounds

  • Follow the recommendation in the Backstage Threat Model to limit access to creating and updating templates
  • Restrict who can create and execute Scaffolder templates using the permissions framework
  • Audit existing templates for symlink usage
  • Run Backstage in a containerized environment with limited filesystem access

References

Severity
7.1 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:L
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@backstage/backend-defaults"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.12.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@backstage/backend-defaults"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.13.0"
            },
            {
              "fixed": "0.13.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@backstage/backend-defaults"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.14.0"
            },
            {
              "fixed": "0.14.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@backstage/plugin-scaffolder-backend"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.2.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@backstage/plugin-scaffolder-backend"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "fixed": "3.0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@backstage/plugin-scaffolder-backend"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.1.0"
            },
            {
              "fixed": "3.1.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@backstage/plugin-scaffolder-node"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.11.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@backstage/plugin-scaffolder-node"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.12.0"
            },
            {
              "fixed": "0.12.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-24046"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22",
      "CWE-59"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-21T22:36:36Z",
    "nvd_published_at": "2026-01-21T23:15:53Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nMultiple Scaffolder actions and archive extraction utilities were vulnerable to symlink-based path traversal attacks. An attacker with access to create and execute Scaffolder templates could exploit symlinks to:\n\n1. **Read arbitrary files** via the `debug:log` action by creating a symlink pointing to sensitive files (e.g., `/etc/passwd`, configuration files, secrets)\n2. **Delete arbitrary files** via the `fs:delete` action by creating symlinks pointing outside the workspace\n3. **Write files outside the workspace** via archive extraction (tar/zip) containing malicious symlinks\n\nThis affects any Backstage deployment where users can create or execute Scaffolder templates.\n\n### Patches\n\nThis vulnerability is fixed in the following package versions:\n\n- `@backstage/backend-defaults` version 0.12.2, 0.13.2, 0.14.1, 0.15.0\n- `@backstage/plugin-scaffolder-backend` version 2.2.2, 3.0.2, 3.1.1\n- `@backstage/plugin-scaffolder-node` version 0.11.2, 0.12.3\n\nUsers should upgrade to these versions or later.\n\n### Workarounds\n\n- Follow the recommendation in the [Backstage Threat Model](https://backstage.io/docs/overview/threat-model#scaffolder) to limit access to creating and updating templates\n- Restrict who can create and execute Scaffolder templates using the permissions framework\n- Audit existing templates for symlink usage\n- Run Backstage in a containerized environment with limited filesystem access\n\n### References\n\n- [CWE-59: Improper Link Resolution Before File Access](https://cwe.mitre.org/data/definitions/59.html)\n- [OWASP Path Traversal](https://owasp.org/www-community/attacks/Path_Traversal)",
  "id": "GHSA-rq6q-wr2q-7pgp",
  "modified": "2026-01-22T15:41:18Z",
  "published": "2026-01-21T22:36:36Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/backstage/backstage/security/advisories/GHSA-rq6q-wr2q-7pgp"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-24046"
    },
    {
      "type": "WEB",
      "url": "https://github.com/backstage/backstage/commit/c641c147ab371a9a8a2f5f67fdb7cb9c97ef345d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/backstage/backstage"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Backstage has a Possible Symlink Path Traversal in Scaffolder Actions"
}



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