CVE-2026-101045 (GCVE-0-2026-101045)

Vulnerability from cvelistv5 – Published: 2026-09-27 17:02 – Updated: 2026-09-28 14:11
VLAI
Title
Fleet Homebrew Cask OS Command Injection via Metadata
Summary
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.
Severity
8.9 (High)
CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
8 (High)
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-28 14:11 UTC
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
References
Impacted products
Vendor Product Version CPE status
fleetdm fleet     cpe:2.3:a:fleetdm:fleet:-:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-11 00:00
Credits
arpitjain099
Show details on NVD website
To clipboard 

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