Description

The software uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize ‘…’ (triple dot) 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

Effectiveness: High

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-2001-0467
  • “…” in web server

• CVE-2001-0615
  • “…” or “….” in chat server

• CVE-2001-0963
  • “…” in cd command in FTP server

• CVE-2001-1193
  • “…” in cd command in FTP server

• CVE-2001-1131
  • “…” in cd command in FTP server

• CVE-2001-0480
  • read of arbitrary files and directories using GET or CD with “…” in Windows-based FTP server.

• CVE-2002-0288
  • read files using “.” and Unicode-encoded “/” or “” characters in the URL.

• CVE-2003-0313
  • Directory listing of web server using “…”

• CVE-2005-1658
  • Triple dot