News
Vigil@nce - QEMU: infinite loop of ehci_advance_state
May 2016 by Vigil@nce
This bulletin was written by Vigil@nce : https://vigilance.fr/offer
SYNTHESIS OF THE VULNERABILITY
An attacker in a guest system can generate an infinite loop in the
ehci_advance_state() function of QEMU, in order to trigger a
denial of service on the host system.
Impacted products: Fedora, QEMU.
Severity: 1/4.
Creation date: 18/04/2016.
DESCRIPTION OF THE VULNERABILITY
The QEMU product emulates USB EHCI (Enhanced Host Controller
Interface).
The ehci_advance_state() function of the hw/usb/hcd-ehci.c file
manipulates a list of SITD (Split Isochronous Transfer
Descriptor). However, if there is a loop in the list, the
ehci_advance_state() function does not end.
An attacker in a guest system can therefore generate an infinite
loop in the ehci_advance_state() function of QEMU, in order to
trigger a denial of service on the host system.
ACCESS TO THE COMPLETE VIGIL@NCE BULLETIN
https://vigilance.fr/vulnerability/QEMU-infinite-loop-of-ehci-advance-state-19399
