CVE-2026-101045

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.

CVSS v3 8.0 HIGH

8.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/fleetdm/fleet/security/advisories/GHSA-fv3p-h7wv-2jgm
https://www.vulncheck.com/advisories/fleet-homebrew-cask-os-command-injection-via-metadata

Configurations

No configuration.

History

27 Sep 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 18:16

Updated : 2026-09-30 18:18

NVD link : CVE-2026-101045

Mitre link : CVE-2026-101045

CVE.ORG link : CVE-2026-101045

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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