Amazon Linux AMI : kernel (ALAS-2018-944)

High Nessus Plugin ID 106171

Synopsis

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

Description

Race condition in raw_sendmsg function allows denial-of-service or kernel addresses leak

A flaw was found in the Linux kernel's implementation of raw_sendmsg allowing a local attacker to panic the kernel or possibly leak kernel addresses. A local attacker, with the privilege of creating raw sockets, can abuse a possible race condition when setting the socket option to allow the kernel to automatically create ip header values and thus potentially escalate their privileges. (CVE-2017-17712)

Use-after-free vulnerability in DCCP socket

A use-after-free vulnerability was found in DCCP socket code affecting the Linux kernel since 2.6.16. This vulnerability could allow an attacker to their escalate privileges. (CVE-2017-8824)

Stack-based out-of-bounds read via vmcall instruction

Linux kernel compiled with the KVM virtualization (CONFIG_KVM) support is vulnerable to an out-of-bounds read access issue. It could occur when emulating vmcall instructions invoked by a guest. A guest user/process could use this flaw to disclose kernel memory bytes.
(CVE-2017-17741)

Unchecked capabilities in net/netfilter/xt_osf.c allows for unprivileged modification to systemwide fingerprint list

net/netfilter/xt_osf.c in the Linux kernel through 4.14.4 does not require the CAP_NET_ADMIN capability for add_callback and remove_callback operations, which allows local users to bypass intended access restrictions because the xt_osf_fingers data structure is shared across all net namespaces. (CVE-2017-17450)

Missing capabilities check in net/netfilter/nfnetlink_cthelper.c allows for unprivileged access to systemwide nfnl_cthelper_list structure

net/netfilter/nfnetlink_cthelper.c in the Linux kernel through 4.14.4 does not require the CAP_NET_ADMIN capability for new, get, and del operations, which allows local users to bypass intended access restrictions because the nfnl_cthelper_list data structure is shared across all net namespaces. (CVE-2017-17448)

Solution

Run 'yum update kernel' to update your system. You will need to reboot your system in order for the new kernel to be running.

See Also

https://alas.aws.amazon.com/ALAS-2018-944.html

Plugin Details

Severity: High

ID: 106171

File Name: ala_ALAS-2018-944.nasl

Version: 3.3

Type: local

Agent: unix

Published: 2018/01/19

Modified: 2018/04/18

Dependencies: 12634

Risk Information

Risk Factor: High

CVSS v2.0

Base Score: 7.2

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

CVSS v3.0

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: 2018/01/18

Reference Information

CVE: CVE-2017-17448, CVE-2017-17450, CVE-2017-17712, CVE-2017-17741, CVE-2017-8824

ALAS: 2018-944