A vulnerability in the DPDK lib/vhost library allows a guest virtual machine to desynchronize the virtqueue size from the inflight descriptor table size, which causes an out-of-bounds write in the host vhost process. This buffer overflow (CWE-787) can corrupt host memory and potentially allow an attacker to alter program execution or crash the vhost subsystem, impacting confidentiality, integrity, and availability of the underlying host.

The flaw impacts Red Hat Fast Datapath on Red Hat Enterprise Linux 8, 9, and 10, as well as the corresponding Red Hat OpenShift Container Platform 4 and Red Hat OpenStack Platform 13 (Queens). The affected components are the DPDK vhost implementation bundled with the Fast Datapath subsystem on these platforms.

The CVSS score of 8.2 indicates high severity, but the EPSS score is below 1%, indicating that publicly known exploitation is rare at the time of reporting. The vulnerability is not listed in CISA’s KEV catalog, which reduces its urgency relative to actively exploited threats. Nevertheless, an out-of-bounds write in privileged host code implies a potentially severe local privilege escalation if an attacker can inject malicious data from a guest. The likely attack vector is a guest virtual machine with vhost enabled; the attacker would need to send crafted data to the host vhost process to trigger the overflow.