Fleet Affected by Local Privilege Escalation via Tcl Command Injection in Orbit

CVE-2026-27806 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

Summary

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.

CWE

  • CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
  • CWE-94: Improper Control of Generation of Code ('Code Injection')

Impact

  • Local privilege escalation to root: Any unprivileged local user on a managed endpoint can execute arbitrary commands as root

Credit

This vulnerability was discovered and reported by bugbunny.ai.

Basic information

Type
reviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2026-04-08 18:03:52 UTC
Updated
2026-06-26 20:20:11 UTC
GitHub reviewed
2026-04-08 18:03:52 UTC
NVD published
2026-04-08

EPSS Score

Score Percentile
0.11% 1.58%

CVSS Scores

Base score Version Severity Vector
7.8 3.1 —
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type Value
GHSA GHSA-rphv-h674-5hp2 ↗
CVE CVE-2026-27806 ↗

CWEs

CWE id Name
CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Credits

  • bugbunny-research (reporter)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
go github.com/fleetdm/fleet/v4 < 4.81.1 4.81.1 —

References

cvelogic Threat Intelligence