Amazon Linux 2 : kernel (ALAS-2020-1405)

medium Nessus Plugin ID 134896
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Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

A flaw was found in the way KVM hypervisor handled instruction emulation for the L2 guest when nested(=1) virtualization is enabled.
In the instruction emulation, the L2 guest could trick the L0 hypervisor into accessing sensitive bits of the L1 hypervisor. An L2 guest could use this flaw to potentially access information of the L1 hypervisor. (CVE-2020-2732)

There is a use-after-free vulnerability in the Linux kernel through 5.5.2 in the n_tty_receive_buf_common function in drivers/tty/n_tty.
(CVE-2020-8648)

Solution

Run 'yum update kernel' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2020-1405.html

Plugin Details

Severity: Medium

ID: 134896

File Name: al2_ALAS-2020-1405.nasl

Version: 1.4

Type: local

Agent: unix

Published: 3/26/2020

Updated: 5/15/2020

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2020-10942

VPR

Risk Factor: Medium

Score: 5.2

CVSS v2

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 4

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

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.6

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

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:kernel-debuginfo, p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:kernel-headers, p-cpe:/a:amazon:linux:kernel-livepatch-4.14.173-137.228, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:python-perf, p-cpe:/a:amazon:linux:python-perf-debuginfo, cpe:/o:amazon:linux:2

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 5/8/2020

Vulnerability Publication Date: 2/6/2020

Reference Information

CVE: CVE-2020-10942, CVE-2020-2732, CVE-2020-8648

ALAS: 2020-1405