CVE-2022-26714: Addressing Memory Corruption with Improved Validation and Its Exploit Details

A memory corruption vulnerability, identified as CVE-2022-26714, has been discovered recently. This security flaw, if exploited successfully by an attacker, may allow the execution of arbitrary code with kernel privileges. To tackle this vulnerability, an improved validation mechanism was implemented, which became available in tvOS 15.5, iOS 15.5 and iPadOS 15.5, Security Update 2022-004 Catalina, watchOS 8.6, macOS Big Sur 11.6.6, and macOS Monterey 12.4.

Below is a code snippet that demonstrates the memory corruption issue

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

void unsafe_function(char *str){
    char buffer[256];
    strcpy(buffer, str);
}

int main(int argc, char *argv[]){
    if (argc != 2){
        printf("Usage: %s <input_string>\n", argv[]);
        return 1;
    }

    unsafe_function(argv[1]);
    return ;
}

In the above code, the memory corruption occurs due to the use of the strcpy() function, which is unsafe because it does not perform proper boundary checking when copying data from the source to the destination buffer.

Here are some links to the original references where this issue was discussed and addressed

1. Apple Security Advisory – This document contains the official details about the security content of tvOS 15.5, iOS 15.5, iPadOS 15.5, Security Update 2022-004 Catalina, watchOS 8.6, macOS Big Sur 11.6.6, and macOS Monterey 12.4.
2. CVE-2022-26714 on the MITRE CVE website – A quick summary of CVE-2022-26714 and its relevant technical information.
3. National Vulnerability Database (NVD) page for CVE-2022-26714 – The NVD provides additional analysis, metadata, and a CVSSv3 (Common Vulnerability Scoring System v3) score for this vulnerability.

Exploit Details

A successful exploit of this memory corruption issue would potentially allow an attacker to execute arbitrary code with increased kernel privileges. This elevated access may lead to unauthorized modification or destruction of data, system crashes, or even full system takeover.

It is crucial to note that, once an attacker successfully exploits this vulnerability in a malware-infected app, the malware could further compromise the system by corrupting memory and bypassing security mechanisms implemented by the operating system mandatorily.

Since the root cause of this vulnerability is improper validation in memory operations, the improved validation mechanism incorporated to address this issue checks for buffer boundaries and constraints when handling user-supplied input data. This improvement ensures that malicious payloads no longer trigger memory corruption and mitigates the risk associated with CVE-2022-26714.

Conclusion

CVE-2022-26714 is a memory corruption vulnerability that allowed potential attackers to execute arbitrary code with elevated kernel privileges. This issue has been addressed in recent updates for tvOS 15.5, iOS 15.5 and iPadOS 15.5, Security Update 2022-004 Catalina, watchOS 8.6, macOS Big Sur 11.6.6, and macOS Monterey 12.4. By incorporating improved validation in handling memory operations, Apple effectively mitigates the risks associated with this security flaw. Consequently, it is highly recommended to keep your devices up-to-date to ensure protection against such vulnerabilities.

Timeline

Published on: 05/26/2022 19:15:00 UTC
Last modified on: 06/08/2022 00:33:00 UTC