RCE in Fleetdm Fleet

CVE-2026-34387

Fleet is open source device management software. Prior to 4.81.1, a command injection vulnerability in Fleet's software installer pipeline allows an attacker to achieve arbitrary code execution as root (macOS/Linux) or SYSTEM (Windows) on managed hosts when an uninstall is triggered for a crafted software package. Version 4.81.1 patches the issue.

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.018 (78.8th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 79th percentile — 78.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-34387: rose from 0.013 to 0.018.

EPSS over last 30 days · oldest: 0.013 · newest: 0.018 · change: +0.006

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-34387?
CVE-2026-34387 is a critical-severity vulnerability in Fleetdm Fleet, classified under OS Command Injection. CVSS score: 9.8/10. Published 2026-03-27.
How severe is CVE-2026-34387?
Critical severity. CVSS v3 base score is 9.8 out of 10.