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                             CERT-Renater

                 Note d'Information No. 2019/VULN279

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DATE                : 12/09/2019

HARDWARE PLATFORM(S): /

OPERATING SYSTEM(S): Systems running Citrix SD-WAN versions prior to
                                10.2.4, 11.0.1,
                        NetScaler SD-WAN versions prior to 10.0.8.

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https://support.citrix.com/article/CTX256918
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Citrix SD-WAN Security Update

Reference: CTX256918

Category : Medium

Created  : 11 Sep 2019

Modified : 11 Sep 2019

Applicable Products

  o Citrix SD-WAN

Description of Problem

Multiple denial of service vulnerabilities have been identified in
the Citrix SD-WAN Appliance and Citrix SD-WAN Center Management Console.
These vulnerabilities could permit a remote attacker to cause a denial
of service by causing a host crash or by causing reduced service
capacity due to resource exhaustion. The vulnerabilities have been
assigned the following CVE numbers.

  o CVE-2019-11477: SACK Panic
  o CVE-2019-11478: SACK Slowness or Excess Resource Usage
  o CVE-2019-11479: Excess Resource Consumption Due to Low MSS Values


Mitigating Factors

In order to protect against these vulnerabilities and web application
related issues, Citrix recommends access to the management console be
restricted. In situations where customers have deployed their management
console in line with industry best practice, network access to this
interface should already be restricted.


Security Best Practices:

10.x - https://docs.citrix.com/en-us/netscaler-sd-wan/10/best-practices/
security-best-practices.html


What Customers Should Do

These vulnerabilities have been addressed in the following software
versions:

o NetScaler SD-WAN 10.0.8

o Citrix SD-WAN 10.2.4

o Citrix SD-WAN 11.0.1

Citrix recommends that customers using vulnerable software upgrade their
management console to the new version or later as soon as possible.

Customers using versions of the product that will not contain a fix
(i.e. 9.3.x) are advised to consider upgrading to a version that does
contain the fix
(i.e. 11.0.1)

The new software versions will be available on the Citrix website.
Information on the available versions can be found at the following
location:

https://www.citrix.com/downloads/netscaler-sd-wan/

In line with general best practice, Citrix also recommends that
customers limit access to the management console of the Citrix SD-WAN
Appliance and Citrix SD-WAN Center Management Console to trusted network
traffic only.


Changelog

+--------------------------------------+--------------------------------------+
|Date                                  |Change
      |
+--------------------------------------+--------------------------------------+
|11th September 2019                   |Initial Publication
      |
+--------------------------------------+--------------------------------------+

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+ CERT-RENATER        | tel : 01-53-94-20-44            +
+ 23/25 Rue Daviel    | fax : 01-53-94-20-41            +
+ 75013 Paris         | email:cert@support.renater.fr   +
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