• Secure Hub shows an error and fails to connect after upgrading to a fixed firmware build to address CVE-2020-8299/ CVE-2020-8300.
• Users can no longer log in to Secure Hub or if already logged in cannot refresh policies.

1. Add a new traffic policy:

Traffic_Pol_SSO_http

2. Click 'Add' beside 'Request Profile' 

3. Call this: 

Traffic_Pro_SSO_http




4. Set this to 'HTTP' and 'Single Sign-on' to 'ON' 

5. Save this.

6. in the 'Expression' section:

if using Advanced policy’s enter:

'true'

if using Classic policy’s enter:

'ns_true'

You can check which version is set here :



Enter the relevant setting - 'true' or 'ns_true' 





7. You may get a warning, click OK 



8. Bind this to the Citrix Gateway For XenMobile\CEM and set this with a large priority number so it it will trigger last and after all existing policy’s 



9. You should see something like this ( you may see more policy’s  depending on the config ) :



Now we need to repeat the process for 'TCP'

10. 

Add a new traffic policy called:

Traffic_Pol_SSO_tcp 


 

11. Click Add beside Request Profile 

12 Call this:

'Traffic_Pro_SSO_tcp'





13. Set the Traffic Profile to 'TCP' and 'Single Sign-On'  to 'ON' 

14. Save this.

15. in the expression section enter ns_true or true depending on what type of policy’s are set 




16. Click OK. You may get a warning again about classic policy, click ok

17. Bind this to the gateway with a large Priority number so it will be evaluated last.



10. Once this is in place.

Test the following:

- Test a new enrollment and see if it and Secure Hub work
- Test an existing enrolment and see if Secure Hub works.

If you encounter an issue with Secure Web and internal web sites make sure both traffic policies are set to last in the priority list.

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Problem Cause

Recent security changes 

https://support.citrix.com/article/CTX297155

 

Description of Problem

Multiple vulnerabilities have been discovered in Citrix ADC (formerly known as NetScaler ADC), Citrix Gateway (formerly known as NetScaler Gateway) and Citrix SD-WAN WANOP appliance models 4000-WO, 4100-WO, 5000-WO, and 5100-WO. These vulnerabilities, if exploited, could result in the following security issues:
  

CVE-ID	Description	CWE	Affected Products	Pre-conditions
CVE-2020-8299	Network-based denial-of-service from within the same Layer 2 network segment	CWE-400: Uncontrolled Resource Consumption	Citrix ADC, Citrix Gateway, Citrix SD-WAN WANOP	The attacker machine must be in the same Layer 2 network segment as the vulnerable appliance
CVE-2020-8300	SAML authentication hijack through a phishing attack to steal a valid user session	CWE-284: Improper access control	Citrix ADC, Citrix Gateway	Citrix ADC or Citrix Gateway must be configured as a SAML SP or a SAML IdP

The following supported versions of Citrix ADC, Citrix Gateway and Citrix SD-WAN WANOP are affected by CVE-2020-8299:
 

• Citrix ADC and Citrix Gateway 13.0 before 13.0-76.29
• Citrix ADC and Citrix Gateway 12.1 before 12.1-61.18
• Citrix ADC and NetScaler Gateway 11.1 before 65.20
• Citrix ADC 12.1-FIPS before 12.1-55.238
• Citrix SD-WAN WANOP 11.4 before 11.4.0
• Citrix SD-WAN WANOP 11.3 before 11.3.2
• Citrix SD-WAN WANOP 11.3 before 11.3.1a
• Citrix SD-WAN WANOP 11.2 before 11.2.3a
• Citrix SD-WAN WANOP 11.1 before 11.1.2c
• Citrix SD-WAN WANOP 10.2 before 10.2.9a

The following supported versions of Citrix ADC and Citrix Gateway are affected by CVE-2020-8300:

• Citrix ADC and Citrix Gateway 13.0. before 13.0-82.41
• Citrix ADC and Citrix Gateway 12.1 before 12.1-62.23
• Citrix ADC and NetScaler Gateway 11.1 before 11.1-65.20
• Citrix ADC 12.1-FIPS before 12.1-55.238

These issues have already been addressed in Citrix-managed cloud services such as Citrix Gateway Service and Citrix Secure Workspace Access. Customers using Citrix-managed services do not need to take any additional action.

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What Customers Should Do

The following supported versions of Citrix ADC, Citrix Gateway, and Citrix SD-WAN WANOP address CVE-2020-8299, a Medium severity vulnerability.  

• Citrix ADC and Citrix Gateway 13.0-76.29 and later releases of 13.0 

• Citrix ADC and Citrix Gateway 12.1-61.18 and later releases of 12.1 

• Citrix ADC and NetScaler Gateway 11.1-65.20 and later releases of 11.1 

• Citrix ADC 12.1-FIPS 12.1-55.238 and later releases of 12.1-FIPS 

• Citrix SD-WAN WANOP 11.4.0 and later releases of 11.4 

• Citrix SD-WAN WANOP 11.3.2 and later releases of 11.3 

• Citrix SD-WAN WANOP 11.3.1a and later releases of 11.3 

• Citrix SD-WAN WANOP 11.2.3a and later releases of 11.2 

• Citrix SD-WAN WANOP 11.1.2c and later releases of 11.1 

• Citrix SD-WAN WANOP 10.2.9a and later releases of 10.2 

The following supported versions of Citrix ADC and Citrix Gateway address CVE-2020-8300, a High severity vulnerability.  

• Citrix ADC and Citrix Gateway 13.0-82.41 and later releases of 13.0 

• Citrix ADC and NetScaler Gateway ADC 12.1-62.23 and later releases of 12.1 

• Citrix ADC and NetScaler Gateway 11.1-65.20 and later releases of 11.1 

• Citrix ADC 12.1-FIPS 12.1-55.238 and later releases of 12.1-FIPS 
   

NOTE: In addition, upon upgrading to the fixed version, customers must modify the device configuration to resolve CVE-2020-8300. See Citrix Application Delivery Controller and Citrix Gateway - SAML Configuration Reference Guide for details. 

Citrix strongly recommends that affected customers install relevant updates as soon as possible. 

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Acknowledgements

Citrix would like to thank ChenNan of Chaitin Security Research Lab, Wolfgang Ettlinger and Marc Nimmerrichter of Certitude Consulting for working with us to protect Citrix customers.

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What Citrix is Doing

Citrix is notifying customers and channel partners about this potential security issue. This article is also available from the Citrix Knowledge Center at https://support.citrix.com/.

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Obtaining Support on This Issue

If you require technical assistance with this issue, please contact Citrix Technical Support. Contact details for Citrix Technical Support are available at https://www.citrix.com/support/open-a-support-case/.

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Reporting Security Vulnerabilities to Citrix

Citrix welcomes input regarding the security of its products and considers any and all potential vulnerabilities seriously. For details on our vulnerability response process and guidance on how to report security-related issues to Citrix, please see the following webpage: https://www.citrix.com/about/trust-center/vulnerability-process.html.

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Disclaimer

This document is provided on an "as is" basis and does not imply any kind of guarantee or warranty, including the warranties of merchantability or fitness for a particular use. Your use of the information on the document is at your own risk. Citrix reserves the right to change or update this document at any time.

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Changelog

Date	Change
2021-06-08	Initial Publication
2021-06-08	Formatting Corrections

 

SEE also :

https://docs.citrix.com/en-us/citrix-adc/current-release/aaa-tm/single-sign-on-types/enable-sso-for-auth-pol.html#citrix-gateway-cases