Input validation and sanitization are fundamental secure coding practices aimed at preventing malicious input from causing harm to a software application. These practices involve checking and filtering user input to ensure it meets expected criteria and is free from potentially harmful characters or code.

Techniques:

Input Validation:
• Validate user input against expected data types, formats, and ranges.
• Check for missing, empty, or invalid input.

Input Sanitization:
• Remove or encode special characters and HTML tags from input to prevent cross-site scripting (XSS) attacks.
• Encode input before storing it in a database to prevent SQL injection attacks.

Buffer overflow protection techniques aim to prevent malicious code from being executed by overflowing a buffer (memory space) in a program. This can lead to security vulnerabilities such as memory corruption and code execution.

Techniques:

Boundary Checking:
• Check the size of input data before copying it into a buffer to prevent buffer overflows.

Safe Programming Languages:
• Use programming languages that employ memory management and boundary checking mechanisms to prevent buffer overflows.

Address Space Layout Randomization (ASLR):
• Randomize the location of key data structures and program code in memory to make it more difficult for attackers to exploit buffer overflows.

Cross-site scripting (XSS) prevention techniques are designed to protect web applications from XSS attacks, where malicious code is injected into a website and executed in a user’s browser.

Techniques:

Input Encoding and Sanitization:
• Encode and sanitize user input before displaying it on a web page to prevent malicious code execution.

Output Encoding:
• Encode data before outputting it to prevent XSS attacks in dynamically generated content.

HTTP Headers:
• Set appropriate HTTP headers to prevent XSS attacks, such as the X-XSS-Protection header.

SQL injection protection techniques prevent malicious SQL queries from being executed by a database, which can lead to unauthorized access to data, data manipulation, and other security breaches.

Techniques:

Parameterized Queries:
• Use parameterized queries or prepared statements to prevent SQL injection attacks by separating SQL commands from user input.

Input Validation:
• Validate user input before using it in SQL queries to prevent malicious characters or code from being executed.

Stored Procedures:
• Use stored procedures to execute predefined SQL queries, reducing the risk of SQL injection attacks.

Memory management and error handling practices ensure that software applications allocate and use memory efficiently, preventing memory corruption and other vulnerabilities.

Techniques:

Memory Allocation and Deallocation:
• Use appropriate memory allocation and deallocation functions to prevent memory leaks and buffer overflows.

Error Handling:
• Implement robust error handling mechanisms to catch and handle errors gracefully, preventing them from causing system crashes or security breaches.

Memory Protection:
• Use memory protection mechanisms, such as data execution prevention (DEP), to prevent malicious code from being executed in memory.