CVE-2026-26191Fleet is open source device management software.

Fleet is open source device management software. Prior to version 4.81.0, a vulnerability in Fleet's software installer pipeline could allow a crafted software package to execute arbitrary commands as root (macOS/Linux) or SYSTEM (Windows) on managed endpoints when an uninstall is triggered. When a software package (.pkg, .deb, .rpm, .exe, or .msi) is uploaded to Fleet, metadata is extracted from the package binary and used to generate uninstall scripts. In affected versions, this metadata is not properly sanitized before being included in the generated scripts. A specially crafted package containing malicious values in its metadata fields could result in unintended command execution when the uninstall script runs on managed endpoints. Version 4.81.0 contains a patch. If an immediate upgrade is not possible, administrators should avoid uploading software packages obtained from untrusted or unverified sources. Additionally, administrators can manually inspect and edit auto-generated uninstall scripts before deployment.

CVSS

9.8 CRITICAL (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness (CWE)

CWE-78

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

Not given

NVD analysis

Analyzed

Record last updated

Jun 17, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.