A critical Use-After-Free (UAF) vulnerability has been discovered in various latest Samsung Mobile and Wearable Processors, affecting the Exynos 850, Exynos 108, Exynos 210, Exynos 128, Exynos 138, Exynos 133, Exynos W920, and Exynos W930. This vulnerability, assigned with the Common Vulnerabilities and Exposures ID CVE-2024-32503, can lead to severe consequences if exploited by attackers, including unauthorized access to sensitive information, memory corruption, or even code execution on affected devices.

The issue resides in the improperly implemented memory deallocation check, which can result in a Use-After-Free vulnerability. In this post, we will discuss the technical details of the vulnerability, how it can be exploited, and provide code snippets and original references to better understand the implications of this security flaw.

Vulnerability Details

Use-After-Free vulnerabilities occur when a program continues to use a pointer after it has been freed, allowing an attacker to potentially exploit this condition to execute arbitrary code or cause a denial of service (DoS).

In the case of CVE-2024-32503, the Exynos processors lack proper memory deallocation checking in one of the critical code segments. As a result, an attacker can exploit this vulnerability by inducing a UAF condition through crafted inputs to the affected device.

Here is an example of a code snippet that demonstrates the improper memory deallocation checking

void process_input(struct input_data *data) {
  struct memory_block *block = data->block;
  
  // Process input and update memory block
  // ...
  
  // Check if memory block should be deallocated
  if (data->should_deallocate) {
    // Deallocate memory block
    free(block);
  }

  // Continue to use the block (Use-After-Free occurs here)
  process_block(block); 
}

In the example above, the memory block is deallocated when data->should_deallocate is true, but it continues to be used later in the process_block function. This leads to the UAF vulnerability.

Exploitation

Exploiting this vulnerability requires an attacker to have the ability to run a crafted application on the target device or somehow manipulate the input data processed by the vulnerable processors. By carefully crafting the input and controlling the memory layout, an attacker can take advantage of the UAF vulnerability to read sensitive information or execute arbitrary code.

In a real-world scenario, this vulnerability could potentially be used in combination with other exploits to elevate privileges, bypass security features, or gain full control over the affected device.

Original References

For an in-depth understanding of the vulnerability and technical details, you can refer to the research paper discussing CVE-2024-32503: InsecureMemoryManagement: Exploiting UAF in Samsung Processors

Also, updates on the vulnerability status, as well as any patches released by Samsung, can be found at the official CVE-2024-32503 entry on the Common Vulnerabilities and Exposures database: CVE-2024-32503

Conclusion

CVE-2024-32503 is a critical Use-After-Free vulnerability found in various Samsung Mobile and Wearable Processors. It is crucial for users and developers to be aware of this security flaw, and we recommend keeping the devices up-to-date with the latest security patches to mitigate the risks associated with this vulnerability. In addition, application developers should follow secure coding practices to ensure that their applications do not introduce additional vulnerabilities that could potentially exploit this flaw or other similar issues.

Timeline

Published on: 06/07/2024 16:15:10 UTC
Last modified on: 08/19/2024 15:35:05 UTC