How Xen Manages Security Disclosure
VIDEO: The Xen Project Advisory Board's chairman discusses how the open-source virtualization technology behind most public clouds is able to patch security issues before they become real problems.The open-source Xen hypervisor has the unique distinction of being the primary virtualization technology that powers most of the world's public cloud computing capacity. That position gives the Xen project the unique opportunity to influence security in a powerful and positive way. In a video interview with eWEEK, Lars Kurth, Xen Project Advisory Board chairman, detailed the history and the current process of how Xen handles security disclosures in a way that protects users, vendors and the Internet at large. When security vulnerabilities are found in any piece of software, the ideal way to fix them is before the general public or attackers are made aware of bugs. Kurth explained that the traditional wisdom in security is to keep any type of predisclosure list for security as small as possible. In Xen's case, the project went through multiple iterations of its security disclosure process, in an attempt to keep things fair for both large and small vendors. In October of 2014, Xen Security Advisory XSA-108 (also identified as CVE-2014-7188) became a case study of how to handle responsible predisclosure to vendors to fix issues and then full disclosure to the general public. In that instance, Amazon, Rackspace and IBM SoftLayer all had to reboot their public clouds to fix a Xen issue. But rather than the issue being one of mass hysteria, it was fixed in an orderly manner, exposing users to little or no risk.
Kurth explained that Xen has a very rapid response time in general, with many security issued patched within a week of being reported. Sometimes it will take cloud providers more time to roll out and implement a patch, which is why it can take as long as three weeks from the time a vulnerability is privately reported to the time it is publicly disclosed.