Amazon Linux 2 : kernel (ALAS-2019-1293)

High Nessus Plugin ID 129392

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VPR Score: 7.4

Synopsis

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

Description

An out-of-bounds access issue was found in the way Linux kernel's KVM hypervisor implements the Coalesced MMIO write operation. It operates on an MMIO ring buffer 'struct kvm_coalesced_mmio' object, wherein write indices 'ring->first' and 'ring->last' value could be supplied by a host user-space process. An unprivileged host user or process with access to '/dev/kvm' device could use this flaw to crash the host kernel, resulting in a denial of service or potentially escalating privileges on the system.(CVE-2019-14821)

A buffer overflow flaw was found in the way Linux kernel's vhost functionality that translates virtqueue buffers to IOVs, logged the buffer descriptors during migration. A privileged guest user able to pass descriptors with invalid length to the host when migration is underway, could use this flaw to increase their privileges on the host.(CVE-2019-14835)

Solution

Run 'yum update kernel' and reboot the instance to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2019-1293.html

Plugin Details

Severity: High

ID: 129392

File Name: al2_ALAS-2019-1293.nasl

Version: 1.4

Type: local

Agent: unix

Published: 2019/09/27

Updated: 2019/12/23

Dependencies: 12634

Risk Information

Risk Factor: High

VPR Score: 7.4

CVSS Score Source: CVE-2019-14835

CVSS v2.0

Base Score: 7.2

Temporal Score: 5.3

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

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

CVSS v3.0

Base Score: 7.8

Temporal Score: 6.8

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: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-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: 2019/10/23

Vulnerability Publication Date: 2019/09/17

Reference Information

CVE: CVE-2019-14821, CVE-2019-14835

ALAS: 2019-1293