Description (CNA)
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 (CNA)
| Vendor / product | Versions |
|---|---|
| fleetdm / fleet | affected 0 before 2026-08-19 |
CWE
CWE-78
References
- https://github.com/fleetdm/fleet/security/advisories/GHSA-fv3p-h7wv-2jgm
- https://www.vulncheck.com/advisories/fleet-homebrew-cask-os-command-injection-via-metadata
ADP enrichment
No English description supplied.
No references supplied.