CVE-2026-75627: Bastillion-Io Bastillion

Critical severity, CVSS 9.8. EPSS: 0.8% chance of exploitation in the next 30 days.

Bastillion fails to properly validate request URI paths in its controller dispatcher, allowing unauthenticated attackers to bypass authentication filters by prefixing requests with arbitrary path segments. Attackers can access administrative controllers to read user listings, create manager accounts, and register managed systems, gaining control over SSH access to the managed fleet.

Affected products

• Bastillion-Io Bastillion: up to and including 5.1.0

Published 2026-08-18. Last modified 2026-09-23.