Weakness · Medium
CWE-57: Path Equivalence: 'fakedir/../realdir/filename'
What it is
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.
- Severity (our rating)
- Medium
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
What an attacker can do
- Read Files or Directories (Confidentiality, Integrity)
- Modify Files or Directories (Confidentiality, Integrity)
How to prevent it
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.
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.