CVE-2023-54081

A flaw was found in the Linux kernel's Xen grant table reclaim mechanism. A remote attacker, by controlling a remote domain in a Xen environment, could exploit this vulnerability. By continuously holding grant references, the attacker can cause the deferred list in the grant table to grow excessively. This leads to a massive memory leak, ultimately resulting in a Denial of Service (DoS) as the guest virtual machine (VM) freezes due to memory exhaustion.

Xen grant table reclaim can accumulate a very large deferred list when a remote domain keeps grant references in use and the local domain cannot end foreign access in time. In such scenarios the deferred list can grow without bounds and cause a massive memory leak that eventually freezes the guest VM. For the CVSS the PR:N choice in the paranoid score assumes an attacker controls a remote domain that interacts with the victim through grant table based protocols and does not require privileges inside the victim OS. It is an inter domain interaction specific to Xen environments and is most relevant for setups like Qubes OS where GUI related behavior can trigger large numbers of deferred grants. Impact is denial of service due to memory exhaustion and VM unresponsiveness.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.