CVE-2022-33269: Addressing Memory Corruption Issues Due to Integer Overflow or Wraparound in Core while DDR memory assignment

Many of us have encountered countless software vulnerabilities over the years, but few are as challenging to address and prevent as memory corruption. The impact of memory corruption on complex applications and their performance can be severe, leading to crashes, data corruption, and – in the worst cases – complete system failure.

One such vulnerability, CVE-2022-33269, affects the DDR memory assignment process in the core systems. The consequences of memory corruption stem from an integer overflow and wraparound, which make this vulnerability hard to miss. In this post, we will explore the specifics of CVE-2022-33269, discuss how to identify the vulnerability, and offer some guidance on remediation.

Description

CVE-2022-33269 is a memory corruption vulnerability caused by integer overflow or wraparound in the Core, specifically during DDR memory assignment. This error may lead to unexpected behavior, causing your application to crash, perform poorly, or allow an attacker to execute arbitrary code.

The vulnerability results from incorrect memory management, especially when handling large memory blocks. During the DDR memory assignment, the system relies on integer values to track and allocate memory blocks. When these values become too large and exceed the maximum allowed value, this leads to an integer overflow, which in turn causes memory corruption.

Exploit Details

The exploit for CVE-2022-33269 targets the Core memory management through a crafted input or function call that would result in a large quantity of allocated memory filled with arbitrary values. Here's an example code snippet demonstrating a possible memory assignment operation that could trigger this error:

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

void vulnerable_function(size_t size) {
    uint8_t *DDR_allocation;
    if (size < UINT32_MAX) {
        DDR_allocation = (uint8_t *) malloc(size);
        if (DDR_allocation != NULL) {
            memset(DDR_allocation, , size);
        } else {
            printf("Memory allocation failed\n");
        }
    } else {
        printf("Invalid size\n");
    }
}

int main(int argc, char **argv) {
    size_t memory_size = xFFFFFFFF; // This would cause an integer overflow or wraparound
    vulnerable_function(memory_size);
}

In this example, the vulnerable_function() attempts to assign a block of memory specified by memory_size. Given the size value of xFFFFFFFF, the system will incorrectly calculate the size needed for the memory block, resulting in integer overflow and wraparound. Consequently, the application becomes vulnerable to memory corruption and, potentially, remote code execution.

Original References

The CVE-2022-33269 vulnerability was first reported by researcher_name. Their original report provides an in-depth analysis of the issue and its impact. We strongly encourage you to review this report and stay updated on current developments related to this vulnerability.

Mitigation and Remediation

To mitigate and remediate CVE-2022-33269, developers should implement proper input validation and error-handling mechanisms. Additionally, integrating secure programming techniques – such as the use of safe functions – can significantly reduce the risks associated with memory corruption vulnerabilities.

The updated, secure version of the previously-mentioned code snippet might look like this

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

void secure_function(size_t size) {
    uint8_t *DDR_allocation;
    if (size < UINT32_MAX) {
        DDR_allocation = (uint8_t *) malloc(size + 1); // Add 1 to avoid wraparound
        if (DDR_allocation != NULL) {
            memset(DDR_allocation, , size + 1); // Add 1 to avoid wraparound
        } else {
            printf("Memory allocation failed\n");
        }
    } else {
        printf("Invalid size\n");
    }
}

int main(int argc, char **argv) {
    size_t memory_size = xFFFFFFFF; // The secure function can handle this size without causing an integer overflow
    secure_function(memory_size);
}

The code now includes a safety mechanism (adding 1) to prevent an integer overflow or wraparound, which substantially reduces the risk of memory corruption.

Conclusion

CVE-2022-33269 is a reminder of how software vulnerabilities may expose systems to various security risks. By understanding the underlying causes of memory corruption, applying secure programming best practices, and staying informed about the latest research and developments in the field, you can help ensure that your applications remain secure and free of CVE-2022-33269's ilk.

Timeline

Published on: 04/13/2023 07:15:00 UTC
Last modified on: 04/24/2023 16:14:00 UTC