Title: EGI SVG 'ALERT' [TLP:WHITE] Linux Kernel DOS vulnerability: TCP SACK
panic CVE-2019-11477 [EGI-SVG-CVE-2019-11477]
Date: 2019-06-20
Updated:
Affected software and risk
==========================
Vulnerability concerning Linux Kernel
Package : Linux Kernel
CVE ID : CVE-2019-11477, CVE-2019-11478, CVE-2019-11479
Three related flaws were found in the Linux kernel's handling of TCP
networking, which could allow a remote attacker to trigger a kernel panic in
systems running the affected software and, as a result, impact the system's
availability. [R 1]
Actions required/recommended
============================
Critical services should either be patched or mitigation should be applied.
Component installation information
==================================
Sites running RedHat should see [R 2]
Sites running Scientific Linux should see [R 3]
Sites running CentOS should see [R 4]
Sites running Ubuntu should see [R 5]
Sites running Debian should see [R 6]
Mitigation
==========
See [R 1]
More information
================
At present SVG is not aware of any public exploits, or any cases where this has
been exploited to compromise availability of services. Therefore we consider
this to be less than 'High' risk at time of writing.
RedHat considers this 'Important' due to the possibility of remote exploit.
Normally, SVG only sends out advisories for issues assessed by SVG as 'High' or
'Critical' risk, but exceptions are made. This is one of these cases, mainly
because this flaw has been talked about in the press e.g. [R 7], and there is
some risk to availability of services due to this issue.
TLP and URL
===========
** WHITE information - Unlimited distribution
- see https://go.egi.eu/tlp for distribution restrictions **
URL: https://advisories.egi.eu/Advisory-SVG-CVE-2019-11477
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 another 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 according to the
procedure defined in [R 8]
Note that this is undergoing revision to fully handle vulnerabilities in the
EOSC-hub era.
References
==========
[R 1] https://access.redhat.com/security/vulnerabilities/tcpsack
[R 2] https://access.redhat.com/security/cve/CVE-2019-11477
[R 3] https://www.scientificlinux.org/category/sl-errata/
[R 4] https://lists.centos.org/pipermail/centos-announce/
[R 5] Ubuntu http://people.canonical.com/~ubuntu-security/cve/2019/CVE-2019-11477.html
[R 6] Debian https://security-tracker.debian.org/tracker/CVE-2019-11477
[R 7] https://www.theregister.co.uk/2019/06/17/linux_tcp_sack_kernel_crash/
[R 8] https://documents.egi.eu/public/ShowDocument?docid=3145
Credit
======
SVG was alerted to this vulnerability by Vincent Brillault
Timeline
========
Yyyy-mm-dd [EGI-SVG-2019-CVE-2019-11477]
2019-06-18 SVG alerted to this issue by Vincent Brillault
2019-06-18 Acknowledgement from the EGI SVG to the reporter
2019-06-19 Not considered 'High' or 'Critical' risk
2019-06-19 Decided to send an Alert to site
2019-06-20 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 8] 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
Note that the SVG issue handling procedure is currently under review, to take
account of the increasing inhomogeneity of the EGI infrastructure and the
services in the EOSC-hub catalogue.
On behalf of the EGI SVG,