CWE-27: Path Traversal: 'dir/../../filename'

VariantDraft

The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize multiple internal "../" sequences that can resolve to a location that is outside of that directory.

View on MITRE
Back to CWE Lookup

Extended Description

This allows attackers to traverse the file system to access files or directories that are outside of the restricted directory. The 'directory/../../filename' manipulation is useful for bypassing some path traversal protection schemes. Sometimes a program only removes one "../" sequence, so multiple "../" can bypass that check. Alternately, this manipulation could be used to bypass a check for "../" at the beginning of the pathname, moving up more than one directory level.

Technical Details

Structure
Simple

Applicable To

Languages
Not Language-Specific
Platforms

Learn More