The Xen Project has released one or more Xen security advisories (XSAs). The security of Qubes OS is affected. Therefore, user action is required.

XSAs that DO affect the security of Qubes OS

The following XSAs do affect the security of Qubes OS:

• XSA-428
• XSA-429

Please see QSB-088 for further details.

XSAs that DO NOT affect the security of Qubes OS

The following XSAs do not affect the security of Qubes OS, and no user action is necessary:

• XSA-427 (Shadow paging is disabled at build time.)

About this announcement

Qubes OS uses the Xen hypervisor as part of its architecture. When the Xen Project publicly discloses a vulnerability in the Xen hypervisor, they issue a notice called a Xen security advisory (XSA). Vulnerabilities in the Xen hypervisor sometimes have security implications for Qubes OS. When they do, we issue a notice called a Qubes security bulletin (QSB). (QSBs are also issued for non-Xen vulnerabilities.) However, QSBs can provide only positive confirmation that certain XSAs do affect the security of Qubes OS. QSBs cannot provide negative confirmation that other XSAs do not affect the security of Qubes OS. Therefore, we also maintain an XSA tracker, which is a comprehensive list of all XSAs publicly disclosed to date, including whether each one affects the security of Qubes OS. When new XSAs are published, we add them to the XSA tracker and publish a notice like this one in order to inform Qubes users that a new batch of XSAs has been released and whether each one affects the security of Qubes OS.