https://seclists.org/oss-sec/2026/q3/670: Xen Security Advisory 509 v3 (CVE-2026-62437) - x86: DMs may cause mem leak by IRQ binding
Affected Software
Frequently Asked Questions
Which guest configurations are exposed?
Only HVM guests with one or more assigned PCI devices can leverage the issue. Environments running only PV guests, or HVM guests without assigned PCI devices, are not exposed to exploitation through this condition.
What does an attacker need to do to trigger the leak?
The attacker needs control of an HVM guest with assigned PCI devices. During guest termination, the guest can cause its device model to bind IRQs again after earlier cleanup has occurred, leaving at least one tracking structure uncollected.
How can I identify systems that need attention?
Identify Xen hosts running HVM guests with PCI devices assigned to them. All Xen versions from at least 3.2 onward are affected; older versions were not inspected.
What is the consequence if the issue is exploited?
The issue leaks hypervisor memory. Repeated exploitation may exhaust host memory and cause denial of service affecting the entire host.