CVE-2018-12026 Phusion Passenger SpawningKit Contains Arbitrary Read/Write Vulnerability
A malicious Passenger-managed application can use symlinks to read or write arbitrary files, leading to information disclosure and privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2018-12026?
CVE-2018-12026 is a critical path traversal vulnerability in n/a, published on 17 Jun 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-59
Which versions are affected by CVE-2018-12026?
2 open source packages ship an affected version, including passenger. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
passenger RubyGems | From 5.3.0 | 5.3.2 |
passenger RubyGems | From 5.3.0 | 5.3.2 |
Products include Phusion Passenger.
How do I fix CVE-2018-12026?
Upgrade passenger to 5.3.2 or later.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2018-12026 being exploited?
There is no known exploitation of CVE-2018-12026 in the wild and no public exploit code.
Other vulnerabilities in n/a
- CVE-2018-12027 Insecure Permissions in Phusion Passenger
- CVE-2018-12028 Incorrect Access Control in Phusion Passenger
- CVE-2016-10345 Phusion Passenger uses a known /tmp filename
- CVE-2012-6135 RubyGems passenger gem allows remote attackers to delete files
- CVE-2025-26803 Phusion Passenger denial of service
Sources
Also known as GHSA-7cv3-gvmc-8mq5.