In the Linux kernel before 4.20.14, expand_downwards in mm/mmap.c lacks a check for the mmap minimum address, which makes it easier for attackers to exploit kernel NULL pointer dereferences on non-SMAP platforms. This is related to a capability check for the wrong task.

In the Linux kernel before 4.20.12, net/ipv4/netfilter/nf_nat_snmp_basic_main.c in the SNMP NAT module has insufficient ASN.1 length checks (aka an array index error), making out-of-bounds read and write operations possible, leading to an OOPS or local privilege escalation. This affects snmp_version and snmp_helper.

In the Linux kernel before 4.20.5, attackers can trigger a drivers/char/ipmi/ipmi_msghandler.c use-after-free and OOPS by arranging for certain simultaneous execution of the code, as demonstrated by a "service ipmievd restart" loop.

In the Linux kernel before 4.20.2, kernel/sched/fair.c mishandles leaf cfs_rq's, which allows attackers to cause a denial of service (infinite loop in update_blocked_averages) or possibly have unspecified other impact by inducing a high load.

A memory leak in the kernel_read_file function in fs/exec.c in the Linux kernel through 4.20.11 allows attackers to cause a denial of service (memory consumption) by triggering vfs_read failures.

In the Linux kernel through 4.20.11, af_alg_release() in crypto/af_alg.c neglects to set a NULL value for a certain structure member, which leads to a use-after-free in sockfs_setattr.

In the Linux kernel before 4.20.8, kvm_ioctl_create_device in virt/kvm/kvm_main.c mishandles reference counting because of a race condition, leading to a use-after-free.

kernel/bpf/verifier.c in the Linux kernel before 4.20.6 performs undesirable out-of-bounds speculation on pointer arithmetic in various cases, including cases of different branches with different state or limits to sanitize, leading to side-channel attacks.

A flaw was found in the Linux kernel's handle_rx() function in the [vhost_net] driver. A malicious virtual guest, under specific conditions, can trigger an out-of-bounds write in a kmalloc-8 slab on a virtual host which may lead to a kernel memory corruption and a system panic. Due to the nature of the flaw, privilege escalation cannot be fully ruled out. Versions from v4.16 and newer are vulnerable.

A flaw was found in the Linux kernel in the function hid_debug_events_read() in drivers/hid/hid-debug.c file which may enter an infinite loop with certain parameters passed from a userspace. A local privileged user ("root") can cause a system lock up and a denial of service. Versions from v4.18 and newer are vulnerable.

The mincore() implementation in mm/mincore.c in the Linux kernel through 4.19.13 allowed local attackers to observe page cache access patterns of other processes on the same system, potentially allowing sniffing of secret information. (Fixing this affects the output of the fincore program.) Limited remote exploitation may be possible, as demonstrated by latency differences in accessing public files from an Apache HTTP Server.

An issue was discovered in can_can_gw_rcv in net/can/gw.c in the Linux kernel through 4.19.13. The CAN frame modification rules allow bitwise logical operations that can be also applied to the can_dlc field. The privileged user "root" with CAP_NET_ADMIN can create a CAN frame modification rule that makes the data length code a higher value than the available CAN frame data size. In combination with a configured checksum calculation where the result is stored relatively to the end of the data (e.g. cgw_csum_xor_rel) the tail of the skb (e.g. frag_list pointer in skb_shared_info) can be rewritten which finally can cause a system crash. Because of a missing check, the CAN drivers may write arbitrary content beyond the data registers in the CAN controller's I/O memory when processing can-gw manipulated outgoing frames.

A use-after-free issue was found in the way the Linux kernel's KVM hypervisor processed posted interrupts when nested(=1) virtualization is enabled. In nested_get_vmcs12_pages(), in case of an error while processing posted interrupt address, it unmaps the 'pi_desc_page' without resetting 'pi_desc' descriptor address, which is later used in pi_test_and_clear_on(). A guest user/process could use this flaw to crash the host kernel resulting in DoS or potentially gain privileged access to a system. Kernel versions before 4.14.91 and before 4.19.13 are vulnerable.

A flaw was found in the Linux kernel's NFS41+ subsystem. NFS41+ shares mounted in different network namespaces at the same time can make bc_svc_process() use wrong back-channel IDs and cause a use-after-free vulnerability. Thus a malicious container user can cause a host kernel memory corruption and a system panic. Due to the nature of the flaw, privilege escalation cannot be fully ruled out.

An issue was discovered in the Linux kernel before 4.19.9. The USB subsystem mishandles size checks during the reading of an extra descriptor, related to __usb_get_extra_descriptor in drivers/usb/core/usb.c.

The userfaultfd implementation in the Linux kernel before 4.19.7 mishandles access control for certain UFFDIO_ ioctl calls, as demonstrated by allowing local users to write data into holes in a tmpfs file (if the user has read-only access to that file, and that file contains holes), related to fs/userfaultfd.c and mm/userfaultfd.c.

An issue was discovered in the Linux kernel before 4.19.3. crypto_report_one() and related functions in crypto/crypto_user.c (the crypto user configuration API) do not fully initialize structures that are copied to userspace, potentially leaking sensitive memory to user programs. NOTE: this is a CVE-2013-2547 regression but with easier exploitability because the attacker does not need a capability (however, the system must have the CONFIG_CRYPTO_USER kconfig option).

In the Linux kernel through 4.19.6, a local user could exploit a use-after-free in the ALSA driver by supplying a malicious USB Sound device (with zero interfaces) that is mishandled in usb_audio_probe in sound/usb/card.c.

The vcpu_scan_ioapic function in arch/x86/kvm/x86.c in the Linux kernel through 4.19.2 allows local users to cause a denial of service (NULL pointer dereference and BUG) via crafted system calls that reach a situation where ioapic is uninitialized.

kvm_pv_send_ipi in arch/x86/kvm/lapic.c in the Linux kernel through 4.19.2 allows local users to cause a denial of service (NULL pointer dereference and BUG) via crafted system calls that reach a situation where the apic map is uninitialized.