How severe is CVE-2026-34387?

CVE-2026-34387 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-34387 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34387?

CVE-2026-34387 affects Fleetdm Fleet. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34387?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-34387 have an EU (EUVD) identifier?

Yes. CVE-2026-34387 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16758.

When was CVE-2026-34387 published?

CVE-2026-34387 was published on 2026-03-27 and last updated on 2026-06-17.

CVE-2026-34387

CVE-2026-34387 is a critical-severity vulnerability in Fleetdm Fleet with a CVSS 3.x base score of 9.8. 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

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 5.7
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-16758
Weakness: CWE-78
Affected product: Fleetdm Fleet
Published: 2026-03-27
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-34387?: CVE-2026-34387 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-34387 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34387?: CVE-2026-34387 affects Fleetdm Fleet. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34387?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-34387 have an EU (EUVD) identifier?: Yes. CVE-2026-34387 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16758.
When was CVE-2026-34387 published?: CVE-2026-34387 was published on 2026-03-27 and last updated on 2026-06-17.

References

https://github.com/fleetdm/fleet/security/advisories/GHSA-7rhw-5mpv-gp4h

Affected products (1)

cpe:2.3:a:fleetdm:fleet:*:*:*:*:*:*:*:*

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