===================================================================== CERT-Renater Note d'Information No. 2021/VULN598 _____________________________________________________________________ DATE : 10/11/2021 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Systems running Citrix ADC and Citrix Gateway versions prior to 13.1-4.43, 13.0-83.27, 12.1-63.22, Citrix ADC and NetScaler Gateway versions prior to 11.1-65.23, Citrix ADC 12.1-FIPS versions prior to 12.1-55.257. ===================================================================== https://support.citrix.com/article/CTX330728 _____________________________________________________________________ CTX330728 Citrix Application Delivery Controller, Citrix Gateway, and Citrix SD-WAN WANOP Edition appliance Security Update Created: 09 Nov 2021 | Modified: 09 Nov 2021 Applicable Products Citrix ADC Citrix Gateway Citrix SD-WAN WANOP Description of Problem Vulnerabilities have been discovered in Citrix ADC (formerly known as NetScaler ADC), 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: CVE-ID  Description  CWE  Affected Products Pre-conditions Criticality CVE-2021-22955 Unauthenticated denial of service CWE-400: Uncontrolled Resource Consumption Citrix ADC, Citrix Gateway Appliance must be configured as a VPN (Gateway) or AAA virtual server Critical CVE-2021-22956 Temporary disruption of the Management GUI, Nitro API and RPC communication CWE-400: Uncontrolled Resource Consumption Citrix ADC, Citrix Gateway, Citrix SD-WAN WANOP Edition Access to NSIP or SNIP with management interface access Low The following supported versions of Citrix ADC and Citrix Gateway are affected by CVE-2021-22955 and CVE-2021-22956: Citrix ADC and Citrix Gateway 13.0 before 13.0-83.27 Citrix ADC and Citrix Gateway 12.1 before 12.1-63.22 Citrix ADC and NetScaler Gateway 11.1 before 11.1-65.23 Citrix ADC 12.1-FIPS before 12.1-55.257 The following supported versions of Citrix SD-WAN WANOP Edition are affected by CVE-2021-22956: Citrix SD-WAN WANOP Edition 11.4 before 11.4.2 Citrix SD-WAN WANOP Edition 10.2 before 10.2.9c Please note that the WANOP feature of SD-WAN Premium Edition is not impacted. This bulletin only applies to customer-managed Citrix ADC, Citrix Gateway and Citrix SD-WAN WANOP Edition appliances. Customers using Citrix-managed cloud services do not need to take any action. What Customers Should Do The following supported versions of Citrix ADC and Citrix Gateway address both CVE-2021-22955 and CVE-2021-22956: Citrix ADC and Citrix Gateway 13.1-4.43 and later releases of 13.1 Citrix ADC and Citrix Gateway 13.0-83.27 and later releases of 13.0 Citrix ADC and Citrix Gateway 12.1-63.22 and later releases of 12.1 Citrix ADC and NetScaler Gateway 11.1-65.23 and later releases of 11.1 Citrix ADC 12.1-FIPS 12.1-55.257 and later releases of 12.1-FIPS The following supported versions of Citrix SD-WAN WANOP Edition address CVE-2021-22956: Citrix SD-WAN WANOP Edition 11.4.2 and later releases of 11.4 Citrix SD-WAN WANOP Edition 10.2.9c and later releases of 10.2 Citrix recommends that affected customers install the relevant update as soon as possible. In addition, upon upgrading to a fixed version, customers must modify the device configuration to resolve CVE-2021-22956. See Citrix Application Delivery Controller, Citrix Gateway, and Citrix SD-WAN WANOP Edition - Management Module Configuration Reference Guide for details. 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/. 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/. 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. 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. Changelog Date Change 2021-11-09 Initial Publication 2021-11-09 Minor formatting changes ========================================================= + 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 + =========================================================