CWE-39 – Path Traversal: ‘C:dirname’

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Description

An attacker can inject a drive letter or Windows volume letter (‘C:dirname’) into a software system to potentially redirect access to an unintended location or arbitrary file.

Modes of Introduction:

– Implementation

 

 

Related Weaknesses

CWE-36

 

Consequences

Integrity, Confidentiality, Availability: Execute Unauthorized Code or Commands

The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.

Integrity: Modify Files or Directories

The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow an attacker to bypass authentication.

Confidentiality: Read Files or Directories

The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing attacks in order to break into an account on the system.

Availability: DoS: Crash, Exit, or Restart

The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the software from working at all and in the case of a protection mechanisms such as authentication, it has the potential to lockout every user of the software.

 

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-2001-0038
    • Remote attackers can read arbitrary files by specifying the drive letter in the requested URL.
  • CVE-2001-0255
    • FTP server allows remote attackers to list arbitrary directories by using the “ls” command and including the drive letter name (e.g. C:) in the requested pathname.
  • CVE-2001-0687
    • FTP server allows a remote attacker to retrieve privileged system information by specifying arbitrary paths.
  • CVE-2001-0933
    • FTP server allows remote attackers to list the contents of arbitrary drives via a ls command that includes the drive letter as an argument.
  • CVE-2002-0466
    • Server allows remote attackers to browse arbitrary directories via a full pathname in the arguments to certain dynamic pages.
  • CVE-2002-1483
    • Remote attackers can read arbitrary files via an HTTP request whose argument is a filename of the form “C:” (Drive letter), “//absolute/path”, or “..” .
  • CVE-2004-2488
    • FTP server read/access arbitrary files using “C:” filenames