A security issue was found in the USB redirection support (usb-redir) of QEMU. More specifically, usb-host and usb-redirect try to batch bulk transfers by combining many small USB packets into a single, large transfer request, to reduce the overhead and improve performance. The combined size of the bulk sending is used in usbredir_handle_bulk_data() to dynamically allocate a variable length array (VLA) on the stack. Since the total size is not bounded, a malicious guest could be able to influence the array length and cause the QEMU process to perform an excessive allocation on the stack, resulting in a denial of service.
A security issue was found in the USB redirection support (usb-redir) of QEMU. More specifically, usb-host and usb-redirect try to batch bulk transfers by combining many small USB packets into a single, large transfer request, to reduce the overhead and improve performance. The combined size of the bulk sending is used in usbredir_handle_bulk_data() to dynamically allocate a variable length array (VLA) on the stack. Since the total size is not bounded, a malicious guest could be able to influence the array length and cause the QEMU process to perform an excessive allocation on the stack, resulting in a denial of service.
https://bugzilla.redhat.com/show_bug.cgi?id=1955695
Vulmon