Permissions, Privileges, and Access Controls in Xen - CVE-2016-4480
Published: May 18, 2016 / Updated: July 28, 2020
Vulnerability identifier: #VU32280
CSH Severity: Low
CVSS v4: 8.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2016-4480
CWE-ID: CWE-264
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local non-authenticated attacker to execute arbitrary code.
The guest_walk_tables function in arch/x86/mm/guest_walk.c in Xen 4.6.x and earlier does not properly handle the Page Size (PS) page table entry bit at the L4 and L3 page table levels, which might allow local guest OS users to gain privileges via a crafted mapping of memory.
Affected software
Xen
xen (Alpine package)
xen
Fedora
xen (Alpine package)
xen
Fedora
How to mitigate CVE-2016-4480
Install update from vendor's website.
xen (Alpine package) - update to 4.4.2-r7
xen - addressed in versions 4.5.3-5.fc23, 4.6.1-9.fc24
xen - addressed in versions 4.5.3-5.fc23, 4.6.1-9.fc24