CVE-2026-34388: Fleet vulnerable to Denial of Service via unhandled gRPC log type in launcher endpoint

March 30, 2026

A Denial of Service vulnerability in Fleet’s gRPC Launcher endpoint allows an authenticated host to crash the entire Fleet server process by sending an unexpected log type value. The server terminates immediately, disrupting all connected hosts, MDM enrollments, and API consumers.

References

github.com/advisories/GHSA-w254-4hp5-7cvv
github.com/fleetdm/fleet
github.com/fleetdm/fleet/security/advisories/GHSA-w254-4hp5-7cvv
nvd.nist.gov/vuln/detail/CVE-2026-34388

Code Behaviors & Features

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