[Forgot Password]
Login  Register Subscribe












Paid content will be excluded from the download.

Download | Alert*
view XML

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

ID: 74Date: (C)2012-05-14   (M)2019-02-08
Type: weaknessStatus: INCOMPLETE
Abstraction Type: Class


The software constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.

Extended Description

Software has certain assumptions about what constitutes data and control respectively. It is the lack of verification of these assumptions for user-controlled input that leads to injection problems. Injection problems encompass a wide variety of issues -- all mitigated in very different ways and usually attempted in order to alter the control flow of the process. For this reason, the most effective way to discuss these weaknesses is to note the distinct features which classify them as injection weaknesses. The most important issue to note is that all injection problems share one thing in common -- i.e., they allow for the injection of control plane data into the user-controlled data plane. This means that the execution of the process may be altered by sending code in through legitimate data channels, using no other mechanism. While buffer overflows, and many other flaws, involve the use of some further issue to gain execution, injection problems need only for the data to be parsed. The most classic instantiations of this category of weakness are SQL injection and format string vulnerabilities.

Likelihood of Exploit: Very High

Applicable Platforms
Language Class: All

Time Of Introduction

  • Architecture and Design
  • Implementation

Related Attack Patterns

Common Consequences

ScopeTechnical ImpactNotes
Read application data
Many injection attacks involve the disclosure of important information -- in terms of both data sensitivity and usefulness in further exploitation.
Bypass protection mechanism
In some cases, injectable code controls authentication; this may lead to a remote vulnerability.
Alter execution logic
Injection attacks are characterized by the ability to significantly change the flow of a given process, and in some cases, to the execution of arbitrary code.
Data injection attacks lead to loss of data integrity in nearly all cases as the control-plane data injected is always incidental to data recall or writing.
Hide activities
Often the actions performed by injected control code are unlogged.

Detection Methods

Potential Mitigations

 Programming languages and supporting technologies might be chosen which are not subject to these issues.
 Utilize an appropriate mix of white-list and black-list parsing to filter control-plane syntax from all input.

In the development view (CWE-699), this is classified as an Input Validation problem (CWE-20) because many people do not distinguish between the consequence/attack (injection) and the protection mechanism that prevents the attack from succeeding. In the research view (CWE-1000), however, input validation is only one potential protection mechanism (output encoding is another), and there is a chaining relationship between improper input validation and the improper enforcement of the structure of messages to other components. Other issues not directly related to input validation, such as race conditions, could similarly impact message structure.

Related CWETypeViewChain
CWE-74 ChildOf CWE-896 Category CWE-888  

Demonstrative Examples

White Box Definitions

Black Box Definitions

Taxynomy Mappings

CLASP  Injection problem ('data' used as something else)
OWASP Top Ten 2004 A6
Injection Flaws


© SecPod Technologies