CVE-2021-47029: 
Linux Kernel vulnerability analysis and mitigation

In the Linux kernel, a vulnerability was discovered in the mt76 connac driver that caused kernel warnings when adding a monitor interface. The issue was identified and assigned CVE-2021-47029. The vulnerability affects Linux kernel versions from 5.12 up to (excluding) 5.12.4 (NVD).

The vulnerability manifests in the mt76_connac_mcu_uni_add_dev routine when attempting to add a monitor interface. The issue stems from missing case handling for monitor interface type in the interface type switch statement. This results in kernel warnings being triggered during the interface addition process. The vulnerability has a CVSS v3.1 Base Score of 5.5 (Medium) with vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (NVD).

When exploited, this vulnerability results in kernel warnings and potential system instability when attempting to add monitor interfaces to the wireless network configuration. While it doesn't lead to information disclosure or system compromise, it can affect system reliability and functionality of wireless networking capabilities.

The vulnerability requires local access and low privileges to exploit. It is triggered through normal system operations when attempting to add a monitor interface to the wireless configuration. No known active exploits have been reported in the wild.

The issue has been fixed through patches that add proper case handling for monitor interface types in the mt76_connac_mcu_uni_add_dev routine. The fix was implemented in kernel commit 2554b9cb4b5e and c996f0346e40e. Users should upgrade to Linux kernel version 5.12.4 or later to address this vulnerability (Kernel Patch).