CWE-57: Path Equivalence: 'fakedir/../realdir/filename'
The product contains protection mechanisms to restrict access to 'realdir/filename', but it constructs pathnames using external input in the form of 'fakedir/../realdir/filename' that are not handled by those mechanisms. This allows attackers to perform unauthorized actions against the targeted file.
How it's found
Path Equivalence: 'fakedir/../realdir/filename' is a specific, narrowly defined instance of a broader pattern. Testers confirm it with targeted code review and a proof-of-concept input that exercises the exact code path this weakness describes.
Consequences
- Read Files or Directories, Modify Files or Directories
Mitigations
- Implementation: Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
Where this fits in a TurboPentest engagement
TurboPentest's agentic pentest is powerful and covers a broad range of issues automatically. This particular class is best confirmed in a manual IntegSec engagement, where human pentesters apply deeper methodology and a larger context window than any automated pass.
Frequently asked questions
What is CWE-57?
The product contains protection mechanisms to restrict access to 'realdir/filename', but it constructs pathnames using external input in the form of 'fakedir/../realdir/filename' that are not handled by those mechanisms. This allows attackers to perform unauthorized actions against the targeted file.
How do you find Path Equivalence: 'fakedir/../realdir/filename'?
Path Equivalence: 'fakedir/../realdir/filename' is a specific, narrowly defined instance of a broader pattern. Testers confirm it with targeted code review and a proof-of-concept input that exercises the exact code path this weakness describes.
What is the impact of CWE-57?
Read Files or Directories, Modify Files or Directories
Does TurboPentest test for Path Equivalence: 'fakedir/../realdir/filename'?
TurboPentest's agentic pentest is powerful and covers a broad range of issues automatically. This particular class is best confirmed in a manual IntegSec engagement, where human pentesters apply deeper methodology and a larger context window than any automated pass.
Related CWEs
About this reference
These security references are maintained by IntegSec, an offensive-security firm whose team holds CISSP, OSCP, and OSCE certifications and has run thousands of penetration tests. Content is kept current as tools, standards, and attack techniques evolve.
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