USN-5002-1: Linux kernel (HWE) vulnerability

Releases

• Ubuntu 18.04 ESM

Packages

• linux-gke-5.3 - Linux kernel for Google Container Engine (GKE) systems
• linux-hwe - Linux hardware enablement (HWE) kernel
• linux-raspi2-5.3 - Linux kernel for Raspberry Pi (V8) systems

Details

Norbert Slusarek discovered a race condition in the CAN BCM networking
protocol of the Linux kernel leading to multiple use-after-free
vulnerabilities. A local attacker could use this issue to execute arbitrary
code.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 18.04

• linux-image-gkeop-5.3 - 5.3.0.75.132
• linux-image-gke-5.3 - 5.3.0.1044.27
• linux-image-5.3.0-1044-gke - 5.3.0-1044.47
• linux-image-5.3.0-1041-raspi2 - 5.3.0-1041.43
• linux-image-5.3.0-75-lowlatency - 5.3.0-75.71
• linux-image-5.3.0-75-generic - 5.3.0-75.71
• linux-image-raspi2-hwe-18.04 - 5.3.0.1041.30

After a standard system update you need to reboot your computer to make
all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.

References

• CVE-2021-3609

Related notices

• USN-4997-1
• USN-4999-1
• USN-5000-1
• USN-5001-1
• USN-5003-1
• USN-5000-2
• USN-4997-2
• LSN-0078-1
• USN-5082-1
• USN-5505-1
• USN-5513-1