CVE-2022-26878: 
Linux Kernel vulnerability analysis and mitigation

CVE-2022-26878 is a memory leak vulnerability discovered in the VirtIO Bluetooth driver of the Linux kernel before version 5.16.3. The vulnerability was disclosed on March 11, 2022, and affects the drivers/bluetooth/virtio_bt.c component. The issue occurs when socket buffers have memory allocated but not freed properly (NVD, Ubuntu).

The vulnerability exists in the virtbtrxhandle function within the VirtIO Bluetooth driver. When packets with an invalid packet type are received, the memory of allocated socket buffers is never freed, leading to a memory leak. This issue has been present since the introduction of the VirtIO transport driver (OSS Security, Kernel Commit).

The vulnerability allows a local attacker with access to the VirtIO counterpart of the driver to create a denial of service condition through memory exhaustion. This can occur when the driver is in use and receiving invalid frames through the driver's interface (Ubuntu).

The vulnerability was fixed in Linux kernel versions 5.16.3 and 5.15.17. The fix involves adding a default case in the switch statement that properly frees these socket buffers when invalid packet types are received (Kernel Commit).