The security vulnerability known as CVE-2023-21127 has been identified in the Android operating system, specifically within the readSampleData function of NuMediaExtractor.cpp. This flaw could potentially lead to remote code execution without requiring any additional execution privileges. It is important to note that user interaction is necessary for successful exploitation. Affected Android versions include Android 11, Android 12, Android 12L, and Android 13. The Android ID for this vulnerability is A-275418191.

Background

NuMediaExtractor.cpp is a component in Android's media processing pipeline. It is responsible for handling media data such as audio and video files. The readSampleData function is used to extract sample data from media files for further processing or playback.

Exploit Details

The vulnerability in question lies in the readSampleData function of NuMediaExtractor.cpp, where uninitialized data can lead to an out-of-bounds write. This condition can be triggered by maliciously crafted media files.

Code Snippet

Below is a code snippet illustrating the vulnerable section of the readSampleData function in NuMediaExtractor.cpp:

status_t NuMediaExtractor::readSampleData(MediaBuffer *buffer) {
     ...
     size_t numBytesRead;
 
     // Uninitialized data can lead to out of bounds write
     status_t err = mImpl->readSampleData(buffer, &numBytesRead);
 
     if (err != OK) {
         return err;
     }
     ...
}


In the code above, the uninitialized data issue can lead to an out-of-bounds write situation. This can be exploited by an attacker to execute arbitrary code on the target device.

Here are links to the original sources containing more information about CVE-2023-21127 and the affected component:

1. Android Open Source Project: https://android.googlesource.com/platform/frameworks/av/+/refs/heads/master/media/libstagefright/NuMediaExtractor.cpp
2. Android Security Bulletin: https://source.android.com/security/bulletin

Possible Impact

Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the target device without requiring any additional execution privileges. This could lead to a compromise of sensitive user data, unauthorized access to the device or network, and other malicious activities.

Mitigation

Google has acknowledged the existence of this vulnerability and has released security updates to fix it. Users are advised to update their Android devices to the latest available security patch to help protect against this issue.

Conclusion

CVE-2023-21127 is a critical vulnerability in Android's NuMediaExtractor.cpp component, which, if exploited, could lead to remote code execution. It is important for users to update their devices with the latest security patches to reduce the risk of exploitation. With the growth of Android devices and their increasing use in various sectors, ensuring the security and privacy of users should always be a top priority for developers and manufacturers alike.

Timeline

Published on: 06/15/2023 19:15:00 UTC
Last modified on: 06/21/2023 13:11:00 UTC