23 Фев, 2024

Insufficient protection against stack underflows

“Insufficient Protection Against Stack Underflows” refers to a security vulnerability where a program or system does not implement adequate measures to prevent stack underflow attacks. Stack underflows occur when the program’s call stack, which is responsible for managing function calls and local variables, is manipulated to go beyond its allocated limits. This can lead to memory corruption, unauthorized access, and potential exploitation by attackers. Here’s a detailed description of this vulnerability:

Stack Underflow Scenario:

Call Stack Operation: During program execution, the call stack is used to manage function calls, local variables, and return addresses.

Insufficient Protection: Stack underflows occur when there is insufficient protection to prevent manipulation of the call stack, causing it to move below its allocated space.

Impact and Exploitation:

Memory Corruption: Manipulating the stack can result in memory corruption, affecting the integrity of local variables and return addresses.

Несанкционированный доступ: Attackers can potentially access sensitive information or execute arbitrary code by exploiting the stack underflow.

Common Causes:

Incorrect Function Calls: Improper function calls or recursion without proper termination conditions can lead to stack underflows.

Buffer Overflows Affecting the Stack: Buffer overflows in local variables can impact the stack, leading to underflows.

Manipulation of Stack Pointers: Attackers may attempt to manipulate stack pointers to move beyond the allocated stack space.

Potential Consequences:

Program Crashes: Stack underflows can cause program crashes or unexpected terminations.

Data Corruption: Local variables and return addresses on the stack may be corrupted, leading to unpredictable behavior.

Security Exploits: Skilled attackers can exploit stack underflows to execute arbitrary code, gain unauthorized access, or compromise system security.

Mitigation Strategies:

Bounds Checking: Implement thorough bounds checking to ensure that stack operations stay within the allocated space.

Safe Function Usage: Utilize secure coding practices and safe function calls to prevent stack underflows.

Static Analysis Tools: Employ static code analysis tools to identify potential stack underflow vulnerabilities during the development phase.

Dynamic Analysis Tools: Use tools like AddressSanitizer or Valgrind to detect runtime memory errors, including stack underflows, during program execution.

Secure Coding Practices: Follow secure coding practices, including avoiding recursive calls without proper termination conditions and validating user inputs.

				
					#include <stdio.h>

void vulnerable_function(int input) {
    int buffer[5];  // Stack-allocated buffer with insufficient bounds checking
    
    // Insufficient protection: No bounds checking on input
    buffer[input] = 42;  // Writing to the stack without proper validation
    
    // ... Rest of the function
}

int main() {
    int user_input;
    
    printf("Enter a value: ");
    scanf("%d", &user_input);
    
    vulnerable_function(user_input);
    
    return 0;
}
				
			

In this example:

В vulnerable_function is designed to perform a certain task, but it includes a stack-allocated buffer with insufficient bounds checking.

The function takes user input (input) without proper validation or bounds checking.

The user input is directly used as an index to write data into the stack-allocated buffer. If the user provides a value outside the bounds of the buffer (e.g., a negative value or a value greater than 4), a stack underflow may occur, leading to unpredictable behavior, memory corruption, or potential security vulnerabilities.

Scanners that detect vulnerability

AFL (American Fuzzy Lop):

Описание: AFL is a powerful fuzzer that automatically discovers vulnerabilities by generating and mutating test cases.

Пример: Use AFL to fuzz test functions and methods that involve stack operations, aiming to identify potential stack underflows.

Valgrind:

Описание: Valgrind is a programming tool for memory debugging, memory leak detection, and profiling.

Пример: Run your program with Valgrind to detect memory-related issues, including potential stack underflows, by analyzing memory access patterns.

AddressSanitizer:

Описание: AddressSanitizer is a runtime memory error detector that finds memory corruption bugs during program execution.

Пример: Compile your program with AddressSanitizer to detect runtime memory errors, including stack underflows, while the code is being executed.

Radamsa:

Описание: Radamsa is a general-purpose fuzzer that generates random or mutated test cases for testing.

Пример: Utilize Radamsa to create diverse input data to test the robustness of your program against unexpected inputs, potentially leading to stack underflows.

GDB (GNU Debugger):

Описание: GDB is a powerful debugger that allows for examining and manipulating the execution of a program.

Пример: Use GDB to step through the execution of your program, examining the call stack and identifying potential stack underflow scenarios.

Average CVSS score

Assigning an average Common Vulnerability Scoring System (CVSS) score specifically for “Insufficient Protection Against Stack Underflows” is challenging because CVSS scores are typically assigned to individual vulnerabilities rather than broader categories. The CVSS score for a vulnerability is influenced by various factors, including the impact, exploitability, and complexity of the specific vulnerability.

CWE information

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer:

Описание: This weakness involves not properly restricting operations within the bounds of a memory buffer, which could include the stack.

Potential Consequences: Memory corruption, unauthorized access, and potential exploitation.

CWE-787: Out-of-bounds Write:

Описание: This weakness involves writing beyond the allocated boundaries of a buffer, which could occur on the stack.

Potential Consequences: Unauthorized access to sensitive data, disclosure of memory contents, and potential security vulnerabilities.

CWE-129: Improper Validation of Array Index:

Описание: This weakness involves not properly validating array indices, which could lead to stack underflows.

Potential Consequences: Memory corruption, unauthorized access, and potential exploitation.

CWE-131: Incorrect Calculation of Buffer Size:

Описание: This weakness involves using an incorrect calculation for the size of a buffer, which could lead to insufficient protection against stack underflows.

Potential Consequences: Memory corruption, unauthorized access, and potential exploitation.

Conclusion and Mitigation

Insufficient protection against stack underflows poses a critical security risk, potentially leading to memory corruption, unauthorized access, and exploitation of software systems. This vulnerability arises when adequate measures are not implemented to prevent manipulation of the call stack, allowing attackers to compromise the integrity and stability of the system.

Key Points:

Memory Corruption Risk: Stack underflows can result in memory corruption, affecting the integrity of local variables and return addresses.

Exploitation Possibilities: Skilled attackers can exploit stack underflows to execute arbitrary code, gain unauthorized access, or compromise system security.

Common Causes: Incorrect function calls, recursion without proper termination conditions, buffer overflows affecting the stack, and manipulation of stack pointers contribute to insufficient protection against stack underflows.

Mitigation Strategies:

Bounds Checking:

Implement robust bounds checking to ensure that stack operations stay within the allocated space.

Safe Function Usage:

Adopt safe library functions and coding practices to prevent stack underflows.

Static Analysis Tools:

Conduct static code analysis to identify potential stack underflow vulnerabilities during the development phase.

Dynamic Analysis Tools:

Utilize tools like AddressSanitizer, Valgrind, or similar tools to detect runtime memory errors, including stack underflows, during program execution.

Secure Coding Practices:

Follow secure coding practices, including avoiding recursive calls without proper termination conditions and validating user inputs.

Regular Security Audits:

Perform security audits и ПЕНТЕСТ to identify and remediate stack underflow vulnerabilities.

Security Education:

Provide ongoing security education for developers to raise awareness about the risks associated with stack underflows and encourage secure coding practices.

Другие Услуги

Готовы к безопасности?

Связаться с нами