Insufficient Filtering of File and Other Resource Names for Executable Content
Weakness ID: 641 (Weakness Variant)Status: Incomplete
+ Description

Description Summary

When an application does not restrict the valid names of resources (e.g. files) supplied by the user, various problems may arise down the line when these resources are used.

Extended Description

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 webpage. Or 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.

+ Time of Introduction
  • Architecture and Design
  • Implementation
+ Applicable Platforms

Languages

All

+ Common Consequences
ScopeEffect
Integrity

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

Availability

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

+ Likelihood of Exploit

Low

+ Enabling Factors for Exploitation

Resource names are controllable by the user.

No sufficient validation of resource names at entry points or before consumption by other processes.

Context where the resources are consumed makes execution of code possible based on the names of the supplied resources.

+ Observed Examples
ReferenceDescription
Format string vulnerability in Dia 0.94 allows user-assisted attackers to cause a denial of service (crash) and possibly execute arbitrary code by triggering errors or warnings, as demonstrated via format string specifiers in a .bmp filename. [CVE-2006-2480 available at: detail.php?alert=CVE-2006-2480 ]
+ Potential Mitigations

Do not allow users to control names of resources used on the server side.

Perform white list input validation at entry points and also before consuming the resources. Reject bad file names rather than trying to cleanse them.

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.

+ Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfWeakness BaseWeakness Base99Improper Control of Resource Identifiers ('Resource Injection')
Development Concepts (primary)699
Research Concepts (primary)1000
+ Content History
Submissions
Submission DateSubmitterOrganizationSource
2008-01-30Evgeny LebanidzeCigitalExternal Submission
Modifications
Modification DateModifierOrganizationSource
2008-09-08CWE Content TeamMITREInternal
updated Common Consequences, Relationships
2008-10-14CWE Content TeamMITREInternal
updated Description
2009-10-29CWE Content TeamMITREInternal
updated Common Consequences