David Vrabel

The issue is related to uncontrolled recursion in Xenstore operations, such as deleting a sub-tree of Xenstore nodes. This can lead to stack exhaustion on xenstored, resulting in a crash. The problem arises when there are sufficiently deep nesting levels.

The issue allows local guest users to cause a denial of service, resulting in a host crash. This can be achieved through vectors involving an uninitialized FIFO-based event channel control block, specifically when binding or moving an event to a different VCPU.