USN-5218-1: Linux kernel (OEM) vulnerabilities
11 January 2022
Several security issues were fixed in the Linux kernel.
Releases
Packages
- 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. (CVE-2021-4204)
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
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.