CVE-2020-29568

Name of the Vulnerable Software and Affected Versions Xen versions through 4.14.x

Description An issue was discovered in some OSes, such as Linux, FreeBSD, and NetBSD, which are processing watch events using a single thread. If the events are received faster than the thread is able to handle, they will get queued. As the queue is unbounded, a guest may be able to trigger an OOM in the backend. All systems with a FreeBSD, Linux, or NetBSD (any version) dom0 are vulnerable.

Recommendations For Xen versions through 4.14.x, consider implementing a queue limit or a mechanism to handle watch events more efficiently to prevent an OOM in the backend. As a temporary workaround, consider restricting the rate at which watch events are received or disabling the single-threaded watch event processing until a patch is available. At the moment, there is no information about a newer version that contains a fix for this vulnerability.