CVE-2018-12028 Incorrect Access Control in Phusion Passenger

What is CVE-2018-12028?

CVE-2018-12028 is a high-severity missing authorization vulnerability in n/a, published on 17 Jun 2018. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

An Incorrect Access Control vulnerability in SpawningKit in Phusion Passenger 5.3.x before 5.3.2 allows a Passenger-managed malicious application, upon spawning a child process, to report an arbitrary different PID back to Passenger's process manager. If the malicious application then generates an error, it would cause Passenger's process manager to kill said reported arbitrary PID.

Weakness: CWE-732

Which versions are affected by CVE-2018-12028?

2 open source packages ship an affected version, including passenger. It affects 1 product.

Products include Phusion Passenger.

How do I fix CVE-2018-12028?

Upgrade passenger to 5.3.2 or later.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2018-12028 being exploited?

There is no known exploitation of CVE-2018-12028 in the wild and no public exploit code.

Other vulnerabilities in n/a

• CVE-2018-12026 Phusion Passenger SpawningKit Contains Arbitrary Read/Write Vulnerability Critical 9.8
• CVE-2018-12027 Insecure Permissions in Phusion Passenger High 8.8
• CVE-2016-10345 Phusion Passenger uses a known /tmp filename High 7.8
• CVE-2012-6135 RubyGems passenger gem allows remote attackers to delete files High 7.5
• CVE-2025-26803 Phusion Passenger denial of service Medium 5.3

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-jjhj-8gx7-x836.