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

The following supported versions of Citrix ADC, Citrix Gateway, and Citrix SD-WAN WANOP Edition are affected by CVE-2021-22919: 

• Citrix ADC and Citrix Gateway 13.0 before 13.0-82.45 
• Citrix ADC and Citrix Gateway 12.1 before 12.1-62.27 
• Citrix ADC and NetScaler Gateway 11.1 before 11.1-65.22
• Citrix ADC 12.1-FIPS before 12.1-55.247
• Citrix SD-WAN WANOP Edition 11.4 before 11.4.0.a
• Citrix SD-WAN WANOP Edition 11.3 before 11.3.2.a
• Citrix SD-WAN WANOP Edition 11.2 before 11.2.3.b
• Citrix SD-WAN WANOP Edition 10.2 before 10.2.9.b 

The following supported versions of Citrix ADC and Citrix Gateway are affected by CVE-2021-22920: 

• Citrix ADC and Citrix Gateway 13.0-82.42 
• Citrix ADC and Citrix Gateway 12.1-62.25 

The following supported versions of Citrix ADC and Citrix Gateway are affected by CVE-2021-22927: 

• Citrix ADC and Citrix Gateway 13.0 before 13.0-82.45
• Citrix ADC and Citrix Gateway 12.1 before 12.1-62.27
• Citrix ADC and NetScaler Gateway 11.1 before 11.1-65.22
• Citrix ADC 12.1-FIPS before 12.1-55.247 

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 Cloud services do not need to take any action.

Instructions

The following supported versions of Citrix ADC, Citrix Gateway and Citrix SD-WAN WANOP Edition address CVE-2021-22919:

• Citrix ADC and Citrix Gateway 13.0-82.45 and later releases of 13.0
• Citrix ADC and Citrix Gateway 12.1-62.27 and later releases of 12.1
• Citrix ADC and NetScaler Gateway 11.1-65.22 and later releases of 11.1
• Citrix ADC 12.1-FIPS 12.1-55.247 and later releases of 12.1-FIPS
• Citrix SD-WAN WANOP Edition 11.4.0a and later releases of 11.4
• Citrix SD-WAN WANOP Edition 11.3.2a and later releases of 11.3
• Citrix SD-WAN WANOP Edition 11.2.3b and later releases of 11.2
• Citrix SD-WAN WANOP Edition 10.2.9b and later releases of 10.2 

The following supported versions of Citrix ADC and Citrix Gateway address CVE-2021-22920 

• Citrix ADC and Citrix Gateway 13.0-82.45 and later releases of 13.0 
• Citrix ADC and Citrix Gateway 12.1-62.27 and later releases of 12.1 

The following supported versions of Citrix ADC and Citrix Gateway address CVE-2021-22927 

• Citrix ADC and Citrix Gateway 13.0-82.45 and later releases of 13.0
• Citrix ADC and Citrix Gateway 12.1-62.27 and later releases of 12.1
• Citrix ADC and NetScaler Gateway 11.1-65.22 and later releases of 11.1
• Citrix ADC 12.1-FIPS 12.1-55.247 and later releases of 12.1-FIPS 

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

If Citrix ADC or Citrix Gateway is configured as a SAML SP, customers must ensure that the device is configured accordingly. See Citrix Application Delivery Controller and Gateway - SAML Configuration Reference Guide for details. Customers who have previously set the SAML configuration according to the document do not need to reapply the configuration changes.

Acknowledgements