RCE in Fleetdm Fleet
CVE-2026-27806
Fleet is open source device management software. Prior to 4.81.1, the Orbit agent's FileVault disk encryption key rotation flow on collects a local user's password via a GUI dialog and interpolates it directly into a Tcl/expect script executed via exec.Command("expect", "-c", script). Because the password is inserted into Tcl brace-quoted send {%s}, a password containing } terminates the literal and injects arbitrary Tcl commands. Since Orbit runs as root, this allows a local unprivileged user to escalate to root privileges. This vulnerability is fixed in 4.81.1.
Vulnerability class: Command Injection (OS Command Injection)
EPSS: 0.001 (1.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Fleetdm Fleet — versions < 4.81.1
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-27806?
- CVE-2026-27806 is a high-severity vulnerability in Fleetdm Fleet, classified under OS Command Injection. CVSS score: 7.8/10. Published 2026-04-08.
- How severe is CVE-2026-27806?
- High severity. CVSS v3 base score is 7.8 out of 10.