Weakness · High
CWE-243: Creation of chroot Jail Without Changing Working Directory
What it is
The product uses the chroot() system call to create a jail, but does not change the working directory afterward. This does not prevent access to files outside of the jail.
- Severity (our rating)
- High
- Likelihood of exploit
- High
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
In more detail
Improper use of chroot() may allow attackers to escape from the chroot jail. The chroot() function call does not change the process's current working directory, so relative paths may still refer to file system resources outside of the chroot jail after chroot() has been called.
What an attacker can do
- Read Files or Directories (Confidentiality)
How to prevent it
MITRE lists no specific mitigation for this weakness. Treat it like its parent weaknesses below: validate input, keep the design simple and review the code where it could appear.
How to find it
- Automated Static Analysis. Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.