CVE-2026-86566 Dpdk: dpdk: guest with runt rx descriptors underflows copy length in vhost enqueue (split and packed rings)
A guest with runt RX descriptors can underflow copy length in vhost enqueue, causing denial of service in shared vhost backends.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-86566?
CVE-2026-86566 is a medium-severity vulnerability in Red Hat Fast Datapath for RHEL 10, published on 14 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A flaw was found in DPDK lib/vhost. A guest with runt RX descriptors can underflow the copy length in vhost enqueue, causing a denial of service in a shared vhost backend such as OVS-DPDK.
Weakness: CWE-191
Which versions are affected by CVE-2026-86566?
How do I fix CVE-2026-86566?
Apply the vendor's patch.
Is CVE-2026-86566 being exploited?
There is no known exploitation of CVE-2026-86566 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-86566, GHSA-qff6-4mmg-g5c9, UBUNTU-CVE-2026-86566.