CAPEC Definitions / CAPEC-139
CAPEC-139: Relative Path Traversal
An attacker exploits a weakness in input validation on the target by supplying a specially constructed path utilizing dot and slash characters for the purpose of obtaining access to arbitrary files or resources. An attacker modifies a known path on the target in order to reach material that is not available through intended channels. These attacks normally involve adding additional path separators (/ or ) and/or dots (.), or encodings thereof, in various combinations in order to reach parent directories or entirely separate trees of the target's directory structure.
Extended Description
No Extended Description.
Mitigations
Design: Input validation. Assume that user inputs are malicious. Utilize strict type, character, and encoding enforcement
Implementation: Perform input validation for all remote content, including remote and user-generated content.
Implementation: Validate user input by only accepting known good. Ensure all content that is delivered to client is sanitized against an acceptable content specification -- using an allowlist approach.
Implementation: Prefer working without user input when using file system calls
Implementation: Use indirect references rather than actual file names.
Implementation: Use possible permissions on file access when developing and deploying web applications.
Relationships with other CAPECs
CAPEC-126: Path Traversal
Prerequisites
The target application must accept a string as user input, fail to sanitize combinations of characters in the input that have a special meaning in the context of path navigation, and insert the user-supplied string into path navigation commands.
Related Weaknesses
CWE-23: Relative Path Traversal
