Debian DSA-4196-1 : linux - security update

High Nessus Plugin ID 109658

Synopsis

The remote Debian host is missing a security-related update.

Description

Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation or denial of service.

- CVE-2018-1087 Andy Lutomirski discovered that the KVM implementation did not properly handle #DB exceptions while deferred by MOV SS/POP SS, allowing an unprivileged KVM guest user to crash the guest or potentially escalate their privileges.

- CVE-2018-8897 Nick Peterson of Everdox Tech LLC discovered that #DB exceptions that are deferred by MOV SS or POP SS are not properly handled, allowing an unprivileged user to crash the kernel and cause a denial of service.

Solution

Upgrade the linux packages.

For the oldstable distribution (jessie), these problems have been fixed in version 3.16.56-1+deb8u1. This update includes various fixes for regressions from 3.16.56-1 as released in DSA-4187-1 (Cf. #897427, #898067 and #898100).

For the stable distribution (stretch), these problems have been fixed in version 4.9.88-1+deb9u1. The fix for CVE-2018-1108 applied in DSA-4188-1 is temporarily reverted due to various regression, cf.
#897599.

See Also

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=897427

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=897599

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=898067

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=898100

https://security-tracker.debian.org/tracker/CVE-2018-1087

https://security-tracker.debian.org/tracker/CVE-2018-8897

https://security-tracker.debian.org/tracker/CVE-2018-1108

https://security-tracker.debian.org/tracker/source-package/linux

https://packages.debian.org/source/jessie/linux

https://packages.debian.org/source/stretch/linux

https://www.debian.org/security/2018/dsa-4196

Plugin Details

Severity: High

ID: 109658

File Name: debian_DSA-4196.nasl

Version: 1.10

Type: local

Agent: unix

Published: 2018/05/10

Updated: 2019/07/15

Dependencies: 12634

Risk Information

Risk Factor: High

CVSS v2.0

Base Score: 7.2

Temporal Score: 6.3

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: CVSS2#E:H/RL:OF/RC:C

CVSS v3.0

Base Score: 7.8

Temporal Score: 7.5

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:H/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:linux, cpe:/o:debian:debian_linux:8.0, cpe:/o:debian:debian_linux:9.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2018/05/08

Vulnerability Publication Date: 2018/05/08

Exploitable With

Metasploit (Microsoft Windows POP/MOV SS Local Privilege Elevation Vulnerability)

Reference Information

CVE: CVE-2018-1087, CVE-2018-8897

DSA: 4196