EGI SVG Advisories

Advisory-SVG-CVE-2016-3841

Title:   EGI SVG Advisory [TLP:WHITE] 'High' risk - Linux kernel's IPv6
         implementation - mishandled socket options [EGI-SVG-CVE-2016-3841]

Date:    2016-12-20
Updated:

Affected software and risk
==========================

'HIGH' risk vulnerability concerning Linux kernel's IPv6 implementation -
mishandled socket options.
The IPv6 stack in the Linux kernel before 4.3.3 mishandles options data, which
allows local users to gain privileges or cause a denial of service
(use-after-free and system crash) via a crafted sendmsg system call.  [R 1]

Note: only IPv6-enabled services with kernels from RedHat 7 or a derivative are
affected.
The vulnerable grid service types are the Worker Node and any shared User
Interface.

Package : Linux kernel
CVE ID  : CVE-2016-3841


Actions required/recommended
============================

Sites running vulnerable services on RedHat 7 or a derivative should update as
soon as possible.

Sites running other versions of the Linux kernel should not be vulnerable, as
the fixes were already in Linux versions mandated to address previous
vulnerabilities.

It is not necessary for sites to respond to this e-mail.


Affected software details
=========================

Sites should see [R 1]

More information
================

Sites should see [R 1] and [R 2]

Mitigation
==========

N/A.


Component installation information
==================================

Sites running RedHat Linux 7 should see [R 1]

Sites running Scientic Linux 7 should see [R 4]


TLP and URL
===========

** WHITE information - Unlimited distribution
- see https://go.egi.eu/tlp for distribution restrictions **

URL:   https://advisories.egi.eu/Advisory-SVG-CVE-2016-3841

Minor updates may be made without re-distribution to the sites

Comments
========

Comments or questions should be sent to svg-rat  at  mailman.egi.eu

If you find or become aware of a vulnerability which is relevant to EGI you may
report it by e-mail to

report-vulnerability at egi.eu

the EGI Software Vulnerability Group will take a look.


Credit
======

SVG was alerted to this vulnerability by Mischa Salle.

References
==========

[R 1] https://access.redhat.com/security/cve/cve-2016-3841

[R 2] https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-3841

[R 3] https://documents.egi.eu/public/ShowDocument?docid=2538

[R 4] https://www.scientificlinux.org/category/sl-errata/slsa-20162574-2/


Timeline
========

Yyyy-mm-dd  [EGI-SVG-CVE-2016-3841]

2016-11-16 SVG alerted to this issue by Mischa Salle
2016-11--- Investigation of vulnerability and relevance to EGI carried out by
           SVG
2016-11-21 EGI SVG Risk Assessment completed
2016-12-14 Update available in Scientific Linux
2016-12-20 Advisory/Alert sent to sites

Context
=======

This advisory has been prepared as part of the effort to fulfil EGI SVG's
purpose "To minimize the risk to the EGI infrastructure arising from software
vulnerabilities"

The risk is that assessed by the group, according to the EGI SVG issue handling
procedure [R 3] in the context of how the software is used in the EGI
infrastructure. It is the opinion of the group, we do not guarantee it to be
correct. The risk may also be higher or lower in other deployments depending on
how the software is used.

Others may re-use this information provided they:-

1) Respect the provided TLP classification

2) Credit the EGI https://www.egi.eu/ Software Vulnerability Group



On behalf of the EGI SVG,