In QEMU 4.1.0, an out-of-bounds read flaw was found in the ATI VGA implementation. It occurs in the ati_cursor_define() routine while handling MMIO write operations through the ati_mm_write() callback. A malicious guest could abuse this flaw to crash the QEMU process, resulting in a denial of service.

iscsi_aio_ioctl_cb in block/iscsi.c in QEMU 4.1.0 has a heap-based buffer over-read that may disclose unrelated information from process memory to an attacker.

rom_copy() in hw/core/loader.c in QEMU 4.0 and 4.1.0 does not validate the relationship between two addresses, which allows attackers to trigger an invalid memory copy operation.

QEMU 4.1.0 has a memory leak in zrle_compress_data in ui/vnc-enc-zrle.c during a VNC disconnect operation because libz is misused, resulting in a situation where memory allocated in deflateInit2 is not freed in deflateEnd.

tftp.c in libslirp 4.1.0, as used in QEMU 4.2.0, does not prevent ..\ directory traversal on Windows.

tcp_emu in tcp_subr.c in libslirp 4.1.0, as used in QEMU 4.2.0, mismanages memory, as demonstrated by IRC DCC commands in EMU_IRC. This can cause a heap-based buffer overflow or other out-of-bounds access which can lead to a DoS or potential execute arbitrary code.

libslirp 4.0.0, as used in QEMU 4.1.0, has a use-after-free in ip_reass in ip_input.c.

Qemu, as used in Xen 4.0, 4.1 and possibly other products, when emulating certain devices with a virtual console backend, allows local OS guest users to gain privileges via a crafted escape VT100 sequence that triggers the overwrite of a "device model's address space."