Amazon Linux AMI : kernel (ALAS-2017-811)

high Nessus Plugin ID 99038
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Synopsis

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

Description

The skbs processed by ip_cmsg_recv() are not guaranteed to be linear (e.g. when sending UDP packets over loopback with MSGMORE). Using csum_partial() on potentially the whole skb len is dangerous; instead be on the safe side and use skb_checksum(). This may lead to an infoleak as the kernel memory may be checksummed and sent as part of the packet. (CVE-2017-6347)

It was discovered that xfrm_replay_verify_len(), as called by xfrm_new_ae(), did not verify that the user-specified replay_window was within the replay state buffer. This allowed for out-of-bounds reads and writes of kernel memory.(CVE-2017-7184)

Solution

Run 'yum update kernel' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2017-811.html

Plugin Details

Severity: High

ID: 99038

File Name: ala_ALAS-2017-811.nasl

Version: 3.2

Type: local

Agent: unix

Published: 3/30/2017

Updated: 4/18/2018

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.2

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

CVSS v3

Risk Factor: High

Base Score: 7.8

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

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-doc, 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

Patch Publication Date: 3/29/2017

Reference Information

CVE: CVE-2017-6347, CVE-2017-7184

ALAS: 2017-811