Description

The software uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize “..” sequences that can resolve to a location that is outside of that directory.

Modes of Introduction:

– Implementation

Related Weaknesses

CWE-23

Consequences

Confidentiality, Integrity: Read Files or Directories, Modify Files or Directories

Potential Mitigations

Phase: Implementation

Description: 

Phase: Implementation

Description: 

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.

CVE References

• CVE-2002-0661
  • “” not in denylist for web server, allowing path traversal attacks when the server is run in Windows and other OSes.

• CVE-2002-0946
  • Arbitrary files may be read files via .. (dot dot) sequences in an HTTP request.

• CVE-2002-1042
  • Directory traversal vulnerability in search engine for web server allows remote attackers to read arbitrary files via “..” sequences in queries.

• CVE-2002-1209
  • Directory traversal vulnerability in FTP server allows remote attackers to read arbitrary files via “..” sequences in a GET request.

• CVE-2002-1178
  • Directory traversal vulnerability in servlet allows remote attackers to execute arbitrary commands via “..” sequences in an HTTP request.