CVE-2018-12026: Phusion Passenger

Critical severity, CVSS 9.8. EPSS: 1.9% chance of exploitation in the next 30 days.

During the spawning of a malicious Passenger-managed application, SpawningKit in Phusion Passenger 5.3.x before 5.3.2 allows such applications to replace key files or directories in the spawning communication directory with symlinks. This then could result in arbitrary reads and writes, which in turn can result in information disclosure and privilege escalation.

Affected products

• Phusion Passenger: from 5.3.0, before 5.3.2 (fixed in 5.3.2)

Published 2018-06-17. Last modified 2026-06-17.