CVE-2026-27806

CVE-2026-27806 is a high-severity vulnerability in Fleetdm Fleet with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.

Key facts

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-27806?
CVE-2026-27806 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-27806 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27806?
CVE-2026-27806 affects Fleetdm Fleet. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-27806?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-27806 have an EU (EUVD) identifier?
Yes. CVE-2026-27806 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20540.
When was CVE-2026-27806 published?
CVE-2026-27806 was published on 2026-04-08 and last updated on 2026-07-25.

References

Affected products (1)

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