Arbitrary Code Execution

xen is vulnerable to arbitrary code execution. The vulnerability exists access rights of Xenstore nodes are per domid, and existing granted access rights are not removed when a domain is being destroyed, allowing a new domain created with the same domid to inherit the access rights to Xenstore nodes from the previous domain(s) with the same domid. Xenstore entries of a guest below /local/domain/ are being deleted by Xen tools when a guest is destroyed, only Xenstore entries of other guests still running are affected.