The previous kernel security update was released three weeks ago. Now the kernel team has released the new one currently available for only Ubuntu 21.04 LTS and 20.04 LTS running the Linux 5.11 kernel series. It is also available for 64-bit, Raspberry Pi, AWS, GCP, Azure, or KVM systems.
Fixing the following security issues
The new Ubuntu kernel security patch brings a fix for
Canonical published a new Linux kernel security update for Ubuntu 21.04 and Ubuntu 20.04 LTS systems running Linux kernel 5.11 to address a total of eight security vulnerabilities. In this new Ubuntu kernel security patch, CVE-2021-3732, a flaw discovered by Alois Wohlschlager in the overlay file system that could allow an attacker to expose sensitive information is fixed. CVE-2021-3739, a security issue affecting the Btrfs file system that allows an attacker with CAP_SYS_ADMIN to cause a DoS. CVE-2021-40490 discovered in the EXT4 file system allows a local attacker to cause DOS or gain administrative privileges.
CVE-2021-42008 is also another security vulnerability discovered in the Linux kernel’s 6pack network protocol driver. The vulnerability allows a privileged attacker to crash the system by causing a DoS or execute arbitrary code. CVE-2020-3702 is a race condition discovered in the Atheros Ath9k Wi-Fi driver. The issue allows an attacker to expose sensitive information from the W-Fi network traffic. CVE-2021-3753, a race condition discovered in the virtual terminal device implementation, leads to an out-of-bounds read vulnerability. It allows a local attacker to expose sensitive information.
Update the kernel urgently
Other than these, CVE-2021-3743 is a security flaw discovered in the Qualcomm IPC Router protocol implementation that allows a local attacker to cause a DoS or expose sensitive information. Lastly, the new kernel security update also fixes CVE-2021-38166 which is an integer overflow discovered in the BPF subsystem. This issue allows a local attacker to cause a DoS or execute arbitrary code.
If you are an Ubuntu 21.04 and Ubuntu 20.04 LTS user using the Linux 5.11 kernel we strongly suggest you update your system to the new kernel versions (linux-image 126.96.36.199.39 for 64-bit) as soon as possible. To upgrade the kernel, run the following command in the Terminal (You can use the Software Updater utility too)
sudo apt update && sudo apt full-upgrade
After the update and upgrading process don’t forget to reboot your computer.