Amazon Linux AMI : kernel (ALAS-2016-772)

High Nessus Plugin ID 95609

Synopsis

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

Description

CVE-2016-8645 kernel: a BUG() statement can be hit in net/ipv4/tcp_input.c

It was discovered that the Linux kernel since 3.6-rc1 with net.ipv4.tcp_fastopen; set to 1 can hit BUG() statement in tcp_collapse() function after making a number of certain syscalls leading to a possible system crash.

CVE-2016-8655 kernel: Race condition in packet_set_ring leads to use after free

A race condition issue leading to a use-after-free flaw was found in the way the raw packet sockets implementation in the Linux kernel networking subsystem handled synchronization while creating the TPACKET_V3 ring buffer. A local user able to open a raw packet socket (requires the CAP_NET_RAW capability) could use this flaw to elevate their privileges on the system.

CVE-2016-9083 kernel: State machine confusion bug in vfio driver leading to memory corruption

A flaw was discovered in the Linux kernel's implementation of VFIO. An attacker issuing an ioctl can create a situation where memory is corrupted and modify memory outside of the expected area. This may overwrite kernel memory and subvert kernel execution.

CVE-2016-9084 kernel: Integer overflow when using kzalloc in vfio driver

The use of a kzalloc with an integer multiplication allowed an integer overflow condition to be reached in vfio_pci_intrs.c. This combined with CVE-2016-9083 may allow an attacker to craft an attack and use unallocated memory, potentially crashing the machine.

Solution

Run 'yum update kernel' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2016-772.html

Plugin Details

Severity: High

ID: 95609

File Name: ala_ALAS-2016-772.nasl

Version: 3.6

Type: local

Agent: unix

Published: 2016/12/08

Updated: 2019/04/11

Dependencies: 12634

Risk Information

Risk Factor: High

CVSS v2.0

Base Score: 7.2

Temporal Score: 6.3

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

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

CVSS v3.0

Base Score: 7.8

Temporal Score: 7.5

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:H/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-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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2016/12/06

Exploitable With

Core Impact

Metasploit (AF_PACKET chocobo_root Privilege Escalation)

Reference Information

CVE: CVE-2016-8645, CVE-2016-8655, CVE-2016-9083, CVE-2016-9084

ALAS: 2016-772