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


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.

Submission Date :

July 19, 2006, midnight

Modification Date :

2023-06-29 00:00:00+00:00

Organization :

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.

Related Weaknesses

This table shows the weaknesses and high level categories that are related to this weakness. These relationships are defined to give an overview of the different insight to similar items that may exist at higher and lower levels of abstraction.

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