CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
13.6%
A flaw was found in the virtio-net device in QEMU. When enabling the RSS feature on the virtio-net network card, the indirections_table data within RSS becomes controllable. Setting excessively large values may cause an index out-of-bounds issue, potentially resulting in heap overflow access. This flaw allows a privileged user in the guest to crash the QEMU process on the host.
A viable mitigation for this vulnerability is to disable RSS on the nic/virtio driver.
This can be performed either with the following qemu-kvm command "-device virtio-net-pci,rss=off", or, alternatively, by directly modifying the KVM XML file to disable RSS using a standard configuration tool (ex. libvirt).