A statement in the System Programming Guide of the Intel 64 and IA-32 Architectures Software Developer's Manual (SDM) was mishandled in the development of some or all operating-system kernels, resulting in unexpected behavior for #DB exceptions that are deferred by MOV SS or POP SS, as demonstrated by (for example) privilege escalation in Windows, macOS, some Xen configurations, or FreeBSD, or a Linux kernel crash. The MOV to SS and POP SS instructions inhibit interrupts (including NMIs), data breakpoints, and single step trap exceptions until the instruction boundary following the next instruction (SDM Vol. 3A; section 6.8.3). (The inhibited data breakpoints are those on memory accessed by the MOV to SS or POP to SS instruction itself.) Note that debug exceptions are not inhibited by the interrupt enable (EFLAGS.IF) system flag (SDM Vol. 3A; section 2.3). If the instruction following the MOV to SS or POP to SS instruction is an instruction like SYSCALL, SYSENTER, INT 3, etc. that tra…

The DPDK vhost-user interface does not check to verify that all the requested guest physical range is mapped and contiguous when performing Guest Physical Addresses to Host Virtual Addresses translations. This may lead to a malicious guest exposing vhost-user backend process memory. All versions before 18.02.1 are vulnerable.

An integer overflow in the implementation of the posix_memalign in memalign functions in the GNU C Library (aka glibc or libc6) 2.26 and earlier could cause these functions to return a pointer to a heap area that is too small, potentially leading to heap corruption.

qemu-nbd in QEMU (aka Quick Emulator) does not ignore SIGPIPE, which allows remote attackers to cause a denial of service (daemon crash) by disconnecting during a server-to-client reply attempt.

Heap-based buffer overflow in Cirrus CLGD 54xx VGA Emulator in Quick Emulator (Qemu) 2.8 and earlier allows local guest OS users to execute arbitrary code or cause a denial of service (crash) via vectors related to a VNC client updating its display after a VGA operation.

The virtqueue_pop function in hw/virtio/virtio.c in QEMU allows local guest OS administrators to cause a denial of service (memory consumption and QEMU process crash) by submitting requests without waiting for completion.

Heap-based buffer overflow in the iscsi_aio_ioctl function in block/iscsi.c in QEMU allows local guest OS users to cause a denial of service (QEMU process crash) or possibly execute arbitrary code via a crafted iSCSI asynchronous I/O ioctl call.

The VGA module in QEMU improperly performs bounds checking on banked access to video memory, which allows local guest OS administrators to execute arbitrary code on the host by changing access modes after setting the bank register, aka the "Dark Portal" issue.

The net_checksum_calculate function in net/checksum.c in QEMU allows local guest OS users to cause a denial of service (out-of-bounds heap read and crash) via the payload length in a crafted packet.

The VNC websocket frame decoder in QEMU allows remote attackers to cause a denial of service (memory and CPU consumption) via a large (1) websocket payload or (2) HTTP headers section.