Amazon Linux AMI : kernel (ALAS-2020-1360)

medium Nessus Plugin ID 135936
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Synopsis

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

Description

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.c.
(CVE-2020-8648)

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)

A stack buffer overflow issue was found in the get_raw_socket() routine of the Host kernel accelerator for virtio net (vhost-net) driver. It could occur while doing an ictol(VHOST_NET_SET_BACKEND) call, and retrieving socket name in a kernel stack variable via get_raw_socket(). A user able to perform ioctl(2) calls on the '/dev/vhost-net' device may use this flaw to crash the kernel resulting in DoS issue. (CVE-2020-10942)

Solution

Run 'yum update kernel' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2020-1360.html

Plugin Details

Severity: Medium

ID: 135936

File Name: ala_ALAS-2020-1360.nasl

Version: 1.3

Type: local

Agent: unix

Published: 4/24/2020

Updated: 4/30/2020

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-i686, 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-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, cpe:/o:amazon:linux

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

Exploit Ease: No known exploits are available

Patch Publication Date: 4/23/2020

Vulnerability Publication Date: 2/6/2020

Reference Information

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

ALAS: 2020-1360