CVE-2018-12029 Phusion Passenger Race Condition Allows Privilege Escalation
Local attackers can escalate privileges via a race condition in Phusion Passenger when using a non-standard instance registry directory with weak permissions.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2018-12029?
CVE-2018-12029 is a high-severity vulnerability in Debian Debian Linux, published on 17 Jun 2018. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-362
Which versions are affected by CVE-2018-12029?
2 open source packages ship an affected version, including passenger. It affects 2 products.
| Package | Affected | Fixed in |
|---|---|---|
passenger RubyGems | From 3.0.0 | 5.3.2 |
passenger RubyGems | From 3.0.0 | 5.3.2 |
Linux distribution packages (1)
rubygem-passenger SUSE:Linux Enterprise Module for Containers 12 | All versions | 5.0.18-12.9.1 |
Products include Debian Debian Linux, Phusion Passenger.
How do I fix CVE-2018-12029?
Upgrade passenger to 5.3.2 or later.
Is CVE-2018-12029 being exploited?
There is no known exploitation of CVE-2018-12029 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as DEBIAN-CVE-2018-12029, GHSA-jjcj-fgfm-9g9r, SUSE-SU-2018:2039-1, UBUNTU-CVE-2018-12029.