Injection

Enhanced Definition

In the mainframe context, **injection** refers to a class of security vulnerabilities where untrusted data is sent to an interpreter as part of a command, query, or script. This can lead to the interpreter executing unintended commands or accessing data without proper authorization, often by manipulating dynamically constructed statements.

Key Characteristics

- Input-Driven Vulnerability: Occurs when an application incorporates user-supplied input directly into a command, query, or script without adequate validation or sanitization.
- Interpreter Exploitation: Targets various interpreters on z/OS, such as SQL parsers for DB2/IMS, JCL interpreters, TSO command processors, or UNIX System Services shell command interpreters.
- Context-Specific: Manifests differently depending on the target interpreter, leading to specific types like SQL Injection for databases or JCL Injection for job control.
- Lack of Input Validation: The primary root cause is insufficient validation, sanitization, or escaping of user-provided data before it is used in a dynamic statement.
- Potential for Severe Impact: Can lead to unauthorized data access, modification, or deletion, system compromise, privilege escalation, or denial-of-service on the mainframe.

Use Cases

- SQL Injection (DB2/IMS): A common scenario where malicious SQL statements are inserted into an application's input fields (e.g., a web application front-end to a DB2 database), leading to unauthorized data access, modification, or deletion in DB2 or IMS databases.
- JCL Injection: Exploiting applications that dynamically generate or modify JCL streams based on user input, allowing an attacker to insert arbitrary JCL statements to execute unauthorized programs, manipulate datasets, or bypass security controls.
- Command Injection: When a mainframe application executes system commands (e.g., TSO commands, UNIX System Services shell commands) constructed using unvalidated user input, enabling an attacker to run arbitrary system commands with the application's privileges.
- LDAP Injection: If a z/OS application interacts with an LDAP directory (e.g., for authentication or authorization) and constructs LDAP queries using unvalidated input, an attacker could manipulate the query to gain unauthorized access or bypass authentication.

Related Concepts

Injection vulnerabilities are a critical aspect of application security on z/OS, directly related to input validation and secure coding practices. They pose a significant threat to data integrity and confidentiality, particularly within database systems like DB2 and IMS, and can compromise system availability by allowing unauthorized execution of JCL or system commands. They highlight the importance of robust security architecture, threat modeling, and access control in the mainframe environment.

Best Practices:

Parameterized Queries/Prepared Statements: For DB2 and IMS database access, always use parameterized queries or prepared statements to separate SQL code from user input, effectively preventing SQL Injection.
**Strict