[USN-5218-1] Linux kernel (OEM) vulnerabilities

========================================================================== Ubuntu Security Notice USN-5218-1 January 11, 2022
linux-oem-5.13 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-5.13: Linux kernel for OEM systems
Details:
Nadav Amit discovered that the hugetlb implementation in the Linux kernel did not perform TLB flushes under certain conditions. A local attacker could use this to leak or alter data from other processes that use huge pages. (CVE-2021-4002)
It was discovered that the eBPF implementation in the Linux kernel did not properly validate the memory size of certain ring buffer operation arguments. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (LP: #1956585)
It was discovered that a race condition existed in the overlay file system implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash). (CVE-2021-20321)
It was discovered that the NFC subsystem in the Linux kernel contained a use-after-free vulnerability in its NFC Controller Interface (NCI) implementation. A local attacker could possibly use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2021-3760)
It was discovered that an integer overflow could be triggered in the eBPF implementation in the Linux kernel when preallocating objects for stack maps. A privileged local attacker could use this to cause a denial of service or possibly execute arbitrary code. (CVE-2021-41864)
It was discovered that the KVM implementation for POWER8 processors in the Linux kernel did not properly keep track if a wakeup event could be resolved by a guest. An attacker in a guest VM could possibly use this to cause a denial of service (host OS crash). (CVE-2021-43056)
It was discovered that the TIPC Protocol implementation in the Linux kernel did not properly validate MSG_CRYPTO messages in some situations. An attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-43267)
It was discovered that the ISDN CAPI implementation in the Linux kernel contained a race condition in certain situations that could trigger an array out-of-bounds bug. A privileged local attacker could possibly use this to cause a denial of service or execute arbitrary code. (CVE-2021-43389)
Update instructions:
The problem can be corrected by updating your system to the following package versions:
Ubuntu 20.04 LTS: linux-image-5.13.0-1026-oem 5.13.0-1026.32 linux-image-oem-20.04c 5.13.0.1026.29
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-5218-1 CVE-2021-20321, CVE-2021-3760, CVE-2021-4002, CVE-2021-41864, CVE-2021-43056, CVE-2021-43267, CVE-2021-43389, launchpad.net/bugs/1956585
Package Information: launchpad.net/ubuntu/+source/linux-oem-5.13/5.13.0-1026.32