Improper Restriction of Names for Files and Other Resources

Incomplete Base
Structure: Simple
Description

The product constructs the name of a file or other resource using input from an upstream component, but it does not restrict or incorrectly restricts the resulting name.

Extended Description

This may produce resultant weaknesses. For instance, if the names of these resources contain scripting characters, it is possible that a script may get executed in the client's browser if the application ever displays the name of the resource on a dynamically generated web page. Alternately, if the resources are consumed by some application parser, a specially crafted name can exploit some vulnerability internal to the parser, potentially resulting in execution of arbitrary code on the server machine. The problems will vary based on the context of usage of such malformed resource names and whether vulnerabilities are present in or assumptions are made by the targeted technology that would make code execution possible.

Common Consequences 2
Scope: IntegrityConfidentialityAvailability

Impact: Execute Unauthorized Code or Commands

Execution of arbitrary code in the context of usage of the resources with dangerous names.

Scope: ConfidentialityAvailability

Impact: Read Application DataDoS: Crash, Exit, or Restart

Crash of the consumer code of these resources resulting in information leakage or denial of service.

Potential Mitigations 3
Phase: Architecture and Design
Do not allow users to control names of resources used on the server side.
Phase: Architecture and Design
Perform allowlist input validation at entry points and also before consuming the resources. Reject bad file names rather than trying to cleanse them.
Phase: Architecture and Design
Make sure that technologies consuming the resources are not vulnerable (e.g. buffer overflow, format string, etc.) in a way that would allow code execution if the name of the resource is malformed.
Likelihood of Exploit

Low

Applicable Platforms
Languages:
Not Language-Specific : Undetermined
Modes of Introduction
Architecture and Design
Implementation
Taxonomy Mapping
  • Software Fault Patterns