CVE-2021-44733

Name of the Vulnerable Software and Affected Versions Linux kernel versions through 5.15.11

Description A use-after-free exists in the TEE subsystem of the Linux kernel due to a race condition in tee shm get from id during an attempt to free a shared memory object. This issue is related to the system call implementation of TEE IOC OPEN SESSION or TEE IOC INVOKE and can be exploited to cause a denial of service or elevate privileges. The vulnerability was found by syzkaller and an exploit for controlling a PC is available, although it does not bypass PAN.

Recommendations For Linux kernel versions through 5.15.11, update to a version newer than 5.15.11 to resolve the issue. As a temporary workaround, consider restricting access to the TEE subsystem to minimize the risk of exploitation.