CVE-2022-50664

Vulnerability

Overview

CVE-2022-50664 describes a memory leak in the Linux kernel's DVB (Digital Video Broadcasting) frontend subsystem. The vulnerability resides in the firmware loading path of certain DVB frontend drivers. When the kernel attempts to load firmware for a DVB frontend device, it allocates memory for the firmware data. If the firmware loading operation fails or is incomplete, the allocated memory is not properly freed, resulting in a memory leak [1][2][3][4].

Exploitation and

Attack Surface

An attacker with local access to the system could trigger the vulnerable firmware loading path repeatedly, for example by repeatedly attaching or initializing DVB frontend devices that require firmware. No special privileges beyond the ability to interact with the DVB subsystem are required. The leak accumulates over time, gradually consuming available kernel memory [1][2].

Impact

A successful exploitation leads to a gradual depletion of kernel memory, which can cause system instability, denial of service (DoS), or a complete system crash. The impact is primarily availability, as the attacker can exhaust memory resources without needing to execute arbitrary code [1][2][3][4].

Mitigation

The fix has been applied in the Linux kernel stable tree. Users should update to a kernel version that includes the commit referenced in the advisory. No workaround is available other than applying the patch or avoiding the use of affected DVB frontend devices [1][2][3][4].