An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It ignores the top byte in the address passed to the brk system call, potentially moving the memory break downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been observed to cause heap corruption with the GNU C Library malloc implementation.

In the Linux kernel 5.4.0-rc2, there is a use-after-free (read) in the __blk_add_trace function in kernel/trace/blktrace.c (which is used to fill out a blk_io_trace structure and place it in a per-cpu sub-buffer).

A memory leak in the fastrpc_dma_buf_attach() function in drivers/misc/fastrpc.c in the Linux kernel before 5.3.9 allows attackers to cause a denial of service (memory consumption) by triggering dma_get_sgtable() failures, aka CID-fc739a058d99.

An out-of-bounds access issue was found in the Linux kernel, all versions through 5.3, in the way Linux kernel's KVM hypervisor implements the Coalesced MMIO write operation. It operates on an MMIO ring buffer 'struct kvm_coalesced_mmio' object, wherein write indices 'ring->first' and 'ring->last' value could be supplied by a host user-space process. An unprivileged host user or process with access to '/dev/kvm' device could use this flaw to crash the host kernel, resulting in a denial of service or potentially escalating privileges on the system.

A certain Red Hat patch for net/ipv4/route.c in the Linux kernel 2.6.18 on Red Hat Enterprise Linux (RHEL) 5 allows remote attackers to cause a denial of service (deadlock) via crafted packets that force collisions in the IPv4 routing hash table, and trigger a routing "emergency" in which a hash chain is too long. NOTE: this is related to an issue in the Linux kernel before 2.6.31, when the kernel routing cache is disabled, involving an uninitialized pointer and a panic.

Array index error in the gdth_read_event function in drivers/scsi/gdth.c in the Linux kernel before 2.6.32-rc8 allows local users to cause a denial of service or possibly gain privileges via a negative event index in an IOCTL request.

The poll_mode_io file for the megaraid_sas driver in the Linux kernel 2.6.31.6 and earlier has world-writable permissions, which allows local users to change the I/O mode of the driver by modifying this file.

Multiple race conditions in fs/pipe.c in the Linux kernel before 2.6.32-rc6 allow local users to cause a denial of service (NULL pointer dereference and system crash) or gain privileges by attempting to open an anonymous pipe via a /proc/*/fd/ pathname.

arch/x86/ia32/ia32entry.S in the Linux kernel before 2.6.31.4 on the x86_64 platform does not clear certain kernel registers before a return to user mode, which allows local users to read register values from an earlier process by switching an ia32 process to 64-bit mode.

The tc_fill_tclass function in net/sched/sch_api.c in the tc subsystem in the Linux kernel 2.4.x before 2.4.37.6 and 2.6.x before 2.6.31-rc9 does not initialize certain (1) tcm__pad1 and (2) tcm__pad2 structure members, which might allow local users to obtain sensitive information from kernel memory via unspecified vectors.