BREW-TRAVIS-CVE-2026-22860 (GHSA-MXW3-3HH2-X2MH)

Vulnerability from osv_homebrew – Published: 2026-08-13 17:44 – Updated: 2026-08-13 17:44 – Source website
VLAI
Summary
Rack has a Directory Traversal via Rack:Directory
Details

Summary

Rack::Directory’s path check used a string prefix match on the expanded path. A request like /../root_example/ can escape the configured root if the target path starts with the root string, allowing directory listing outside the intended root.

Details

In directory.rb, File.expand_path(File.join(root, path_info)).start_with?(root) does not enforce a path boundary. If the server root is /var/www/root, a path like /var/www/root_backup passes the check because it shares the same prefix, so Rack::Directory will list that directory also.

Impact

Information disclosure via directory listing outside the configured root when Rack::Directory is exposed to untrusted clients and a directory shares the root prefix (e.g., public2, www_backup).

Mitigation

  • Update to a patched version of Rack that correctly checks the root prefix.
  • Don't name directories with the same prefix as one which is exposed via Rack::Directory.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": null,
        "range_state": "affected",
        "resource": "rack",
        "resource_purl": "pkg:gem/rack@3.0.11",
        "upstream_fixed_in": "3.1.20"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "travis",
        "purl": "pkg:brew/travis"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "registry",
    "upstream_evidence": [
      {
        "ecosystem": "RubyGems",
        "key": "pkg:gem/rack@3.0.11",
        "name": "rack",
        "resource": "rack",
        "strategy": "registry",
        "subject_version": "3.0.11"
      }
    ]
  },
  "details": "## Summary\n\n`Rack::Directory`\u2019s path check used a string prefix match on the expanded path. A request like `/../root_example/` can escape the configured root if the target path starts with the root string, allowing directory listing outside the intended root.\n\n## Details\n\nIn `directory.rb`, `File.expand_path(File.join(root, path_info)).start_with?(root)` does not enforce a path boundary. If the server root is `/var/www/root`, a path like `/var/www/root_backup` passes the check because it shares the same prefix, so `Rack::Directory` will list that directory also. \n\n## Impact\n\nInformation disclosure via directory listing outside the configured root when `Rack::Directory` is exposed to untrusted clients and a directory shares the root prefix (e.g., `public2`, `www_backup`).\n\n## Mitigation\n\n* Update to a patched version of Rack that correctly checks the root prefix.\n* Don\u0027t name directories with the same prefix as one which is exposed via `Rack::Directory`.",
  "id": "BREW-travis-CVE-2026-22860",
  "modified": "2026-08-13T17:44:53Z",
  "published": "2026-08-13T17:44:53Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/rack/rack/security/advisories/GHSA-mxw3-3hh2-x2mh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-22860"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rack/rack/commit/75c5745c286637a8f049a33790c71237762069e7"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/rack/rack"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/rack/CVE-2026-22860.yml"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Rack has a Directory Traversal via Rack:Directory",
  "upstream": [
    "GHSA-mxw3-3hh2-x2mh",
    "CVE-2026-22860"
  ]
}



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