Fleet Homebrew Cask OS Command Injection via Metadata

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-101045",
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-09-27T17:02:34.472Z",
    "dateReserved": "2026-09-27T15:48:49.472Z",
    "datePublished": "2026-09-27T17:02:34.472Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck",
        "dateUpdated": "2026-09-27T17:02:34.472Z"
      },
      "datePublic": "2026-09-11T00:00:00.000Z",
      "title": "Fleet Homebrew Cask OS Command Injection via Metadata",
      "descriptions": [
        {
          "lang": "en",
          "value": "Fleet-maintained app install and uninstall scripts for macOS are generated from Homebrew cask metadata. In manifests generated before 2026-08-19, the script generator escaped this metadata at some interpolation sites but not all of them, so cask metadata containing shell metacharacters (for example $(...) command substitution) could be carried into scripts that execute as root on managed macOS hosts. An attacker who could land crafted metadata in an upstream Homebrew cask — without needing any Fleet credentials — could achieve arbitrary command execution as root on managed macOS hosts that install or uninstall the affected Fleet-maintained app; exploitation required the crafted metadata to pass both upstream Homebrew cask review and Fleet's review of the automated ingestion pull request. The fix (fleetdm/fleet#51324) landed in Fleet's ingestion pipeline on 2026-08-19 so that all manifests generated on or after that date escape cask metadata at every interpolation site; because manifests are generated centrally and distributed as pre-built content, remediation applied to all deployments with no customer action, and the code fix is included in Fleet v4.92.0."
        }
      ],
      "affected": [
        {
          "vendor": "fleetdm",
          "product": "fleet",
          "defaultStatus": "unaffected"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')",
              "cweId": "CWE-78",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/fleetdm/fleet/security/advisories/GHSA-fv3p-h7wv-2jgm",
          "name": "GitHub Security Advisory (GHSA-fv3p-h7wv-2jgm)",
          "tags": [
            "vendor-advisory"
          ]
        },
        {
          "url": "https://www.vulncheck.com/advisories/fleet-homebrew-cask-os-command-injection-via-metadata",
          "name": "VulnCheck Advisory: Fleet Homebrew Cask OS Command Injection via Metadata",
          "tags": [
            "third-party-advisory"
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS"
        },
        {
          "format": "CVSS",
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H",
            "attackVector": "NETWORK",
            "attackComplexity": "HIGH",
            "privilegesRequired": "HIGH",
            "userInteraction": "NONE",
            "scope": "CHANGED",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "availabilityImpact": "HIGH",
            "baseScore": 8,
            "baseSeverity": "HIGH"
          }
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "arpitjain099",
          "type": "reporter"
        }
      ]
    }
  }
}