Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS : Intel Microcode vulnerabilities (USN-3756-1)

medium Nessus Plugin ID 112151

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

It was discovered that memory present in the L1 data cache of an Intel CPU core may be exposed to a malicious process that is executing on the CPU core. This vulnerability is also known as L1 Terminal Fault (L1TF). A local attacker in a guest virtual machine could use this to expose sensitive information (memory from other guests or the host OS). (CVE-2018-3646)

Jann Horn and Ken Johnson discovered that microprocessors utilizing speculative execution of a memory read may allow unauthorized memory reads via a sidechannel attack. This flaw is known as Spectre Variant 4. A local attacker could use this to expose sensitive information, including kernel memory. (CVE-2018-3639)

Zdenek Sojka, Rudolf Marek, Alex Zuepke, and Innokentiy Sennovskiy discovered that microprocessors that perform speculative reads of system registers may allow unauthorized disclosure of system parameters via a sidechannel attack. This vulnerability is also known as Rogue System Register Read (RSRE). An attacker could use this to expose sensitive information. (CVE-2018-3640).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Update the affected intel-microcode package.

See Also

https://ubuntu.com/security/notices/USN-3756-1

Plugin Details

Severity: Medium

ID: 112151

File Name: ubuntu_USN-3756-1.nasl

Version: 1.10

Type: local

Agent: unix

Published: 8/28/2018

Updated: 10/21/2023

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 4.7

Temporal Score: 3.7

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

CVSS Score Source: CVE-2018-3646

CVSS v3

Risk Factor: Medium

Base Score: 5.6

Temporal Score: 5.1

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

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

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:intel-microcode, cpe:/o:canonical:ubuntu_linux:14.04:-:lts, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 8/27/2018

Vulnerability Publication Date: 5/22/2018

Reference Information

CVE: CVE-2018-3639, CVE-2018-3640, CVE-2018-3646

USN: 3756-1