|Description||Another race in XENMAPSPACE_grant_table handling Guests are permitted access to certain Xen-owned pages of memory. The majority of such pages remain allocated / associated with a guest for its entire lifetime. Grant table v2 status pages, however, are de-allocated when a guest switches (back) from v2 to v1. Freeing such pages requires that the hypervisor enforce that no parallel request can result in the addition of a mapping of such a page to a guest. That enforcement was missing, allowing guests to retain access to pages that were freed and perhaps re-used for other purposes. Unfortunately, when XSA-379 was being prepared, this similar issue was not noticed.|
|Source||CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more)|
Vulnerable and fixed packages
The table below lists information on source packages.
|xen (PTS)||stretch (security), stretch||4.8.5.final+shim4.10.4-1+deb9u12||vulnerable|
|buster, buster (security)||4.11.4+107-gef32c7afa2-1||vulnerable|
The information below is based on the following data on fixed versions.
|Package||Type||Release||Fixed Version||Urgency||Origin||Debian Bugs|
[buster] - xen <end-of-life> (DSA 4677-1)
[stretch] - xen <end-of-life> (DSA 4602-1)