Description

The __switch_to function in arch/x86/kernel/process_64.c in the Linux kernel does not properly context-switch IOPL on 64-bit PV Xen guests, which allows local guest OS users to gain privileges, cause a denial of service (guest OS crash), or obtain sensitive information by leveraging I/O port access.

References

http://www.debian.org/security/2016/dsa-3607

http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html

http://www.securityfocus.com/bid/84594

http://www.securitytracker.com/id/1035308

http://www.ubuntu.com/usn/USN-2968-1

http://www.ubuntu.com/usn/USN-2968-2

http://www.ubuntu.com/usn/USN-2969-1

http://www.ubuntu.com/usn/USN-2970-1

http://www.ubuntu.com/usn/USN-2971-1

http://www.ubuntu.com/usn/USN-2971-2

http://www.ubuntu.com/usn/USN-2971-3

http://www.ubuntu.com/usn/USN-2996-1

http://www.ubuntu.com/usn/USN-2997-1

http://xenbits.xen.org/xsa/advisory-171.html

Details

Risk Information

CVSS v2

CVSS v3