# CVE-2018-12029: libapache2-mod-passenger: A race condition in the nginx module in Phusion Passenger 3.x through 5.x before 5.3.2 allows local escalation of pri...

CVE-2018-12029 is fixed in 3 products on 1 platform, first by libapache2-mod-passenger 5.0.30-1+deb9u1build0.18.04.1, released June 17, 2018. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-12029
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0027
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 17, 2018

## Description

A race condition in the nginx module in Phusion Passenger 3.x through 5.x before 5.3.2 allows local escalation of privileges when a non-standard passenger_instance_registry_dir with insufficiently strict permissions is configured. Replacing a file with a symlink after the file was created, but before it was chowned, leads to the target of the link being chowned via the path. Targeting sensitive files such as root's crontab file allows privilege escalation.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libapache2-mod-passenger Ubuntu 18.04.6 LTS (bionic) | 5.0.30-1+deb9u1build0.18.04.1 | [libapache2-mod-passenger 5.0.30-1+deb9u1build0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libapache2-mod-passenger-5.0.30-1-deb9u1build0.18.04.1.md) | Jun 17, 2018 |
| Linux | passenger Ubuntu 18.04.6 LTS (bionic) | 5.0.30-1+deb9u1build0.18.04.1 | [passenger 5.0.30-1+deb9u1build0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-passenger-5.0.30-1-deb9u1build0.18.04.1.md) | Jun 17, 2018 |
| Linux | ruby-passenger Ubuntu 18.04.6 LTS (bionic) | 5.0.30-1+deb9u1build0.18.04.1 | [ruby-passenger 5.0.30-1+deb9u1build0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-ruby-passenger-5.0.30-1-deb9u1build0.18.04.1.md) | Jun 17, 2018 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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