[USN-4947-1] Linux kernel (OEM) vulnerabilities

========================================================================== Ubuntu Security Notice USN-4947-1 May 11, 2021
linux-oem-5.6 vulnerabilities ==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
– Ubuntu 20.04 LTS
Summary:
Several security issues were fixed in the Linux kernel.
Software Description: – linux-oem-5.6: Linux kernel for OEM systems
Details:
Kiyin (尹亮) discovered that the x25 implementation in the Linux kernel contained overflows when handling addresses from user space. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-35519)
It was discovered that the fastrpc driver in the Linux kernel did not prevent user space applications from sending kernel RPC messages. A local attacker could possibly use this to gain elevated privileges. (CVE-2021-28375)
It was discovered that the TIPC protocol implementation in the Linux kernel did not properly validate passed encryption key sizes. A local attacker could use this to cause a denial of service (system crash). (CVE-2021-29646)
It was discovered that a race condition existed in the netfilter subsystem of the Linux kernel when replacing tables. A local attacker could use this to cause a denial of service (system crash). (CVE-2021-29650)
Arnd Bergmann discovered that the video4linux subsystem in the Linux kernel did not properly deallocate memory in some situations. A local attacker could use this to cause a denial of service (memory exhaustion). (CVE-2021-30002)
Update instructions:
The problem can be corrected by updating your system to the following package versions:
Ubuntu 20.04 LTS: linux-image-5.6.0-1056-oem 5.6.0-1056.60 linux-image-oem-20.04 5.6.0.1056.52
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: ubuntu.com/security/notices/USN-4947-1 CVE-2020-35519, CVE-2021-28375, CVE-2021-29646, CVE-2021-29650, CVE-2021-30002
Package Information: launchpad.net/ubuntu/+source/linux-oem-5.6/5.6.0-1056.60