The BPF subsystem in the Linux kernel before 4.17 mishandles
situations with a long jump over an instruction sequence where inner
instructions require substantial expansions into multiple BPF instructions,
leading to an overflow. This affects kernel/bpf/core.c and
net/core/filter.c.(CVE-2018-25020)
Maxim Levitsky discovered that the KVM hypervisor implementation for AMD
processors in the Linux kernel did not properly prevent a guest VM from
enabling AVIC in nested guest VMs. An attacker in a guest VM could use this
to write to portions of the host's physical memory.(CVE-2021-3653)
Nadav Amit discovered that the hugetlb implementation in the
Jann Horn discovered that the tty subsystem of the Linux kernel did not use
consistent locking in some situations, leading to a read-after-free
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly expose sensitive information (kernel memory).(CVE-2020-29660)
Jann Horn discovered a race condition in the tty subsystem of the Linux
kernel in the locking for the TIOCSPGRP ioctl(), leading to a use-after-
free vulnerability. A local attacker could use this to cause a denial of
service (system crash) or possibly execute arbitrary code.(CVE-2020-29661)
De4dCr0w of 360 Alpha Lab discovered that the
Maxim Levitsky discovered that the KVM hypervisor implementation for AMD
processors in the Linux kernel did not properly prevent a guest VM from
enabling AVIC in nested guest VMs. An attacker in a guest VM could use this
to write to portions of the host's physical memory.(CVE-2021-3653)
Maxim Levitsky and Paolo Bonzini discovered that the KVM hypervisor
implementation for AMD processors in the Linux kernel allowed a guest VM to
disable restrictions on VMLOAD/VMSAVE in a nested guest. An attacker in a
guest VM could use this to read or write portions of the host's physical
memory.(CVE-2021-3656)
Andy Nguyen discovered that the netfilter subs
Andy Nguyen discovered that the netfilter subsystem in the Linux kernel
contained an out-of-bounds write in its setsockopt() implementation. A
local attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code.(CVE-2021-22555)
It was discovered that the eBPF implementation in the Linux kernel did not
properly track bounds information for 32 bit registers when performing div
and mod operations. A local attacker could use this to possibly execute
arbitrary code.(CVE-2021-3600)
It was discovered that the virtual file system implementation in the Linux
kernel contained an unsigned to signed integer conversion error. A local
attacker could use this to cause a denial of service (system crash) or
execute arbitrary code.(CVE-2021-33909)
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.(CVE-2021-3609)
Vincent Dehors discovered that the shiftfs file system in the Ubuntu Linux
kernel did not properly handle faults in copy_from_user() when passing
through ioctls to an underlying file system. A local attacker could use
this to cause a denial of service (memory exhaustion) or execute arbitrary
code.(CVE-2021-3492)
It was discovered that the overlayfs implementation in the Linux kernel did
not properly validate the application of file system capabilities with
respect to user namespaces. A local attacker could use this to gain
elevated privileges.(CVE-2021-3493)
Piotr Krysiuk discovered that the BPF JIT compiler for x86 in the Linux
kernel did not properly validate computation of branch displacements in
some situations. A local attacker could use this to cause a denial of
service (system crash) or possibly execute arbitrary code.(CVE-2021-29154)