SB2016050931 - Information disclosure in xen (Alpine package)
Published: May 9, 2016
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Information disclosure (CVE-ID: CVE-2016-3159)
The vulnerability allows a local authenticated user to gain access to sensitive information.
The fpu_fxrstor function in arch/x86/i387.c in Xen 4.x does not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allows local guest OS users to obtain sensitive register content information from another guest by leveraging pending exception and mask bits. NOTE: this vulnerability exists because of an incorrect fix for CVE-2013-2076.
Remediation
Install update from vendor's website.
References
- https://git.alpinelinux.org/aports/commit/?id=08e33d0f02c353d47b25b57f4f56a6ba9918fe32
- https://git.alpinelinux.org/aports/commit/?id=6ee4459a5f8f1757470b868e4874677e31fbb3fd
- https://git.alpinelinux.org/aports/commit/?id=2e04022d1a3fe8b9e3ff2e830cfeca39b4b610aa
- https://git.alpinelinux.org/aports/commit/?id=bc2fd89aabfb7b623b4c283950bb456c6724a931
- https://git.alpinelinux.org/aports/commit/?id=40a3ee6c24583c262a4a8390459526dc40832862