Description
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.
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.
Modes of Introduction:
– Architecture and Design
Likelihood of Exploit: High
Related Weaknesses
Consequences
Confidentiality: Read Application Data
Many injection attacks involve the disclosure of important information — in terms of both data sensitivity and usefulness in further exploitation.
Access Control: Bypass Protection Mechanism
In some cases, injectable code controls authentication; this may lead to a remote vulnerability.
Other: 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.
Integrity, Other: Other
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.
Non-Repudiation: Hide Activities
Often the actions performed by injected control code are unlogged.
Potential Mitigations
Phase: Requirements
Effectiveness:
Description:
Programming languages and supporting technologies might be chosen which are not subject to these issues.
Phase: Implementation
Effectiveness:
Description:
Utilize an appropriate mix of allowlist and denylist parsing to filter control-plane syntax from all input.
CVE References