Improper Control of Resource Identifiers ('Resource Injection')
Weakness ID: 99 (Weakness Base)Status: Draft
+ Description

Description Summary

The software receives input from an upstream component, but it does not restrict or incorrectly restricts the input before it is used as an identifier for a resource that may be outside the intended sphere of control.

Extended Description

This may enable an attacker to access or modify otherwise protected system resources.

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

Languages

All

+ Likelihood of Exploit

High

+ Demonstrative Examples

Example 1

The following Java code uses input from an HTTP request to create a file name. The programmer has not considered the possibility that an attacker could provide a file name such as "../../tomcat/conf/server.xml", which causes the application to delete one of its own configuration files.

(Bad Code)
Example Language: Java 
String rName = request.getParameter("reportName");
File rFile = new File("/usr/local/apfr/reports/" + rName);
...
rFile.delete();

Example 2

The following code uses input from the command line to determine which file to open and echo back to the user. If the program runs with privileges and malicious users can create soft links to the file, they can use the program to read the first part of any file on the system.

(Bad Code)
Example Language: C++ 
ifstream ifs(argv[0]);
string s;
ifs >> s;
cout << s;

The kind of resource the data affects indicates the kind of content that may be dangerous. For example, data containing special characters like period, slash, and backslash, are risky when used in methods that interact with the file system. (Resource injection, when it is related to file system resources, sometimes goes by the name "path manipulation.") Similarly, data that contains URLs and URIs is risky for functions that create remote connections.

+ Potential Mitigations

Assume all input is malicious. Use an appropriate combination of black lists and white lists to ensure only valid and expected input is processed by the system.

+ Other Notes

A resource injection issue occurs when the following two conditions are met: 1. An attacker can specify the identifier used to access a system resource. For example, an attacker might be able to specify part of the name of a file to be opened or a port number to be used. 2. By specifying the resource, the attacker gains a capability that would not otherwise be permitted. For example, the program may give the attacker the ability to overwrite the specified file, run with a configuration controlled by the attacker, or transmit sensitive information to a third-party server. Note: Resource injection that involves resources stored on the filesystem goes by the name path manipulation and is reported in separate category. See the path manipulation description for further details of this vulnerability.

+ Weakness Ordinalities
OrdinalityDescription
Primary
(where the weakness exists independent of other weaknesses)
+ Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfWeakness ClassWeakness Class20Improper Input Validation
Seven Pernicious Kingdoms (primary)700
ChildOfWeakness ClassWeakness Class74Failure to Sanitize Data into a Different Plane ('Injection')
Development Concepts (primary)699
Research Concepts (primary)1000
PeerOfWeakness ClassWeakness Class706Use of Incorrectly-Resolved Name or Reference
Research Concepts1000
CanAlsoBeWeakness ClassWeakness Class73External Control of File Name or Path
Research Concepts1000
ParentOfWeakness VariantWeakness Variant641Insufficient Filtering of File and Other Resource Names for Executable Content
Development Concepts (primary)699
Research Concepts (primary)1000
MemberOfViewView630Weaknesses Examined by SAMATE
Weaknesses Examined by SAMATE (primary)630
PeerOfWeakness BaseWeakness Base621Variable Extraction Error
Research Concepts1000
+ Causal Nature

Explicit

+ Taxonomy Mappings
Mapped Taxonomy NameNode IDFitMapped Node Name
7 Pernicious KingdomsResource Injection
+ Related Attack Patterns
CAPEC-IDAttack Pattern Name
(CAPEC Version: 1.4)
10Buffer Overflow via Environment Variables
75Manipulating Writeable Configuration Files
+ White Box Definitions

A weakness where the code path has:

1. start statement that accepts input followed by

2. a statement that allocates a System Resource using name where the input is part of the name

3. end statement that accesses the System Resource where

a. the name of the System Resource violates protection

+ Content History
Submissions
Submission DateSubmitterOrganizationSource
7 Pernicious KingdomsExternally Mined
Modifications
Modification DateModifierOrganizationSource
2008-07-01Eric DalciCigitalExternal
updated Time of Introduction
2008-08-01KDM AnalyticsExternal
added/updated white box definitions
2008-09-08CWE Content TeamMITREInternal
updated Relationships, Other Notes, Taxonomy Mappings, Weakness Ordinalities
2009-05-27CWE Content TeamMITREInternal
updated Description, Name
2009-07-17KDM AnalyticsExternal
Improved the White Box Definition
2009-07-27CWE Content TeamMITREInternal
updated White Box Definitions
Previous Entry Names
Change DatePrevious Entry Name
2008-04-11Resource Injection
2009-05-27Insufficient Control of Resource Identifiers (aka 'Resource Injection')