Attention! Please note the following regarding to this update:
Customers who already have transitioned to Netscaler LAS can upgrade without any special remarks. If you have not yet changed the Licensing mode, please check the requirements for LAS prior to the update!
Upgrading without proper LAS activation can lead to licensing issues. While these can be resolved by downloading a new file-based license, this workaround is only available until April 15, 2026.
Severity – Critical
Description of Problem
Vulnerabilities have been discovered in NetScaler ADC (formerly Citrix ADC) and NetScaler Gateway (formerly Citrix Gateway). Refer below for further details.
Affected Versions:
The following supported versions of NetScaler ADC and NetScaler Gateway are affected by the vulnerabilities:
CVE-2026-3055:
NetScaler ADC and NetScaler Gateway 14.1 BEFORE 14.1-66.59
NetScaler ADC and NetScaler Gateway 13.1 BEFORE 13.1-62.23
NetScaler ADC FIPS and NDcPP BEFORE 13.1-37.262
CVE-2026-4368:
NetScaler ADC and NetScaler Gateway 14.1-66.54
Note: This bulletin only applies to customer-managed NetScaler ADC and NetScaler Gateway. Cloud Software Group upgrades Citrix-managed cloud services and Citrix-managed Adaptive Authentication with the necessary software updates.
Details
NetScaler ADC and NetScaler Gateway are affected by the vulnerabilities mentioned below:
CVE-ID
Description
Pre-conditions
CWE
CVSS v4.0
CVE-2026-3055
Insufficient input validation leading to memory overread
Citrix ADC or Citrix Gateway must be configured as a SAML IDP
CWE-125: Out-of-bounds Read
CVSS v4.0 Base Score: 9.3(CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L)
CVE-2026-4368
Race Condition leading to User Session Mixup
Appliance must be configured as:Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server
CWE-362: Race Condition
CVSS v4.0 Base Score: 7.7(CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N)
What Customers Should Do
CVE 2026-3055 was identified internally through our ongoing security reviews and broader efforts to strengthen the security of the product.
Cloud Software Group strongly urges affected customers of NetScaler ADC and NetScaler Gateway to install the relevant updated versions as soon as possible.
NetScaler ADC and NetScaler Gateway 14.1-66.59 and later releases
NetScaler ADC and NetScaler Gateway 13.1-62.23 and later releases of 13.1
NetScaler ADC 13.1-FIPS and 13.1-NDcPP 13.1.37.262 and later releases of 13.1-FIPS and 13.1-NDcPP
Note: Customers are recommended to upgrade their appliances to one of the supported versions that address the vulnerabilities.
CVE-2026-3055 :
Customers can determine if they have an appliance configured as a SAML IDP Profile by inspecting their NetScaler Configuration for the specified string:
add authentication samlIdPProfile .*
CVE-2026-4368
Customers can determine if they have an appliance configured as one of the following by inspecting their NetScaler Configuration for the specified strings
An Auth Server (AAA Vserver):
add authentication vserver .*
A Gateway (VPN Vserver, ICA Proxy, CVPN, RDP Proxy) :
Vor eingen Tagen hat Citrix eine MaIl an alle Kunden verschickt, mit der Information, dass ab dem 15. April 2026 das alte Lizenzmodell mit lokalen Lizenzfiles nicht mehr unterstützt wird. Statt dessen soll ab dann zwingend der neue License Activation Service (LAS) genutzt werden.
Kunden werden aufgefordert, baldmöglichst auf das neue LAS Lizenzverfahren umzustellen. Diese Umstellung erfordert ein Update aller Citrix Komponenten auf mindestens CR 2411, oder neuer.
Unglücklicherweise treten bei diversen Produkten nach der Installation Lizenzierungsprobleme auf. Welche Probleme auftreten, hängt von diversen Parametern ab. So spielt das Alter der lokalen Lizenzfiles, aber auch das Lizenzmodell (Universal, HMC, Citrix for Private Cloud, etc.) eine Rolle. Zusammen mit den unterschiedliche Citrix Produkten (CVAD, PVS, Lizenz Server, XenServer, etc.) ergibt sich eine recht grosse Matrix mit unterschiedlichsten Problemen.
Bei diversen Kunden wurden teils gravierende Probleme entdeckt. So funktioniert nach dem Update auf 2507 LTSR, abhängig vom Lizenzmodell, entweder PVS nicht mehr, siehe https://support.citrix.com/external/article/695191/citrix-provisioning-services-reports-the.html, oder alle Mitarbeiter erhalten in ihrer Citrix Session ein Pop-Up mit der Info, dass die Umgebung ungenügend lizenziert ist und in 30 Tagen aufhört zu funktionieren.
AXACOM empfiehlt daher allen Kunden, momentan keine Updates ihrer CVAD-, Lizenz- und PVS-Server durchzuführen und zu warten, bis die Probleme behoben sind.
A vulnerability has been discovered in NetScaler ADC (formerly Citrix ADC) and NetScaler Gateway (formerly Citrix Gateway). Refer below for further details.
Affected Versions
The following supported versions of NetScaler ADC and NetScaler Gateway are affected by the vulnerabilities:
NetScaler ADC and NetScaler Gateway 14.1 BEFORE 14.1-47.46
NetScaler ADC and NetScaler Gateway 13.1 BEFORE 13.1-59.19
NetScaler ADC 13.1-FIPS and NDcPP BEFORE 13.1-37.236-FIPS and NDcPP
NetScaler ADC 12.1-FIPS is not affected by this vulnerability.
Note: NetScaler ADC and NetScaler Gateway versions 12.1 and 13.0 are now End Of Life (EOL) and are vulnerable. Customers are recommended to upgrade their appliances to one of the supported versions that address the vulnerabilities.
Additional Note: Secure Private Access on-prem or Secure Private Access Hybrid deployments using NetScaler instances are also affected by the vulnerabilities. Customers need to upgrade these NetScaler instances to the recommended NetScaler builds to address the vulnerabilities.
This bulletin only applies to customer-managed NetScaler ADC and NetScaler Gateway. Cloud Software Group upgrades the Citrix-managed cloud services and Citrix-managed Adaptive Authentication with the necessary software updates.
Details
NetScaler ADC and NetScaler Gateway contain the vulnerability mentioned below:
CVE-ID
Description
Pre-conditions
CWE
CVSSv4
CVE-2025-6543
Memory overflow vulnerability leading to unintended control flow and Denial of Service
NetScaler must be configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server
CWE-119 – Improper Restriction of Operations within the Bounds of a Memory Buffer
CVSS v4.0 Base Score: 9.2(CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L)
What Customers Should Do
Exploits of CVE-2025-6543 on unmitigated appliances have been observed.
Cloud Software Group strongly urges affected customers of NetScaler ADC and NetScaler Gateway to install the relevant updated versions as soon as possible.
NetScaler ADC and NetScaler Gateway 14.1-47.46 and later releases
NetScaler ADC and NetScaler Gateway 13.1-59.19 and later releases of 13.1
NetScaler ADC 13.1-FIPS and 13.1-NDcPP 13.1-37.236 and later releases of 13.1-FIPS and 13.1-NDcPP. Customers should contact support – https://support.citrix.com/support-home/home to obtain the 13.1-FIPS and 13.1-NDcPP builds that address this issue.
Note: NetScaler ADC and NetScaler Gateway versions 12.1 and 13.0 are now End Of Life (EOL) and no longer supported. Customers are recommended to upgrade their appliances to one of the supported versions that address the vulnerabilities.
A vulnerability has been discovered in the Citrix Secure Access Client for Windows. Refer to below for further details:
Affected Versions
The following supported versions of Citrix Secure Access Client for Windows are affected:
Citrix Secure Access Client for Windows versions BEFORE 25.5.1.15
Disclaimer
The information on this page is being provided to you on an «AS IS» and «AS-AVAILABLE» basis. The issues described on this page may or may not impact your system(s). Cloud Software Group, Inc. and its subsidiaries (collectively, «Cloud SG») make no representations, warranties, or guarantees as to the information contained herein. ANY AND ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY, NON-INFRINGEMENT AND FITNESS FOR A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. BY ACCESSING THIS PAGE, YOU ACKNOWLEDGE THAT CLOUD SG SHALL IN NO EVENT BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES THAT ARISE OUT OF YOUR USE OR FAILURE TO USE THE INFORMATION CONTAINED HEREIN. Cloud SG reserves the right to change or update the information on this page at any time. We accordingly recommend that you always view the latest version of this page. The information contained herein is being provided to you under the terms of your applicable customer agreement with Cloud SG, and may be used only for the purposes contemplated by such agreement. If you do not have such an agreement with Cloud SG, this information is provided under the cloud.com Terms of Use, and may be used only for the purposes contemplated by such Terms of Use.
Details
Citrix Secure Access Client for Windows contains a vulnerability mentioned below
CVE-ID
Description
Pre-conditions
CWE
CVSSv4
CVE-2025-0320
Local Privilege escalation allows a low-privileged user to gain SYSTEM privileges
Standard user access on local system
CWE-269: Improper Privilege Management
CVSS v4.0 Base Score: 8.5 (CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N)
What Customers Should Do
Cloud Software Group strongly urges customers of Citrix Secure Access Client for Windows to install the relevant updated versions as soon as possible:
Citrix Secure Access Client for Windows 25.5.1.15 and later releases
Acknowledgements
Cloud Software Group thanks Damien Foulde of Axians for working with us to protect Cloud Software Group customers.
A vulnerability has been discovered in NetScaler ADC (formerly Citrix ADC) and NetScaler Gateway (formerly Citrix Gateway). Refer below for further details.
Affected Versions
The following supported versions of NetScaler ADC and NetScaler Gateway are affected by the vulnerabilities:
NetScaler ADC and NetScaler Gateway 14.1 BEFORE 14.1-43.56
NetScaler ADC and NetScaler Gateway 13.1 BEFORE 13.1-58.32
NetScaler ADC 13.1-FIPS and NDcPP BEFORE 13.1-37.235-FIPS and NDcPP
NetScaler ADC 12.1-FIPS BEFORE 12.1-55.328-FIPS
Note: NetScaler ADC and NetScaler Gateway versions 12.1 and 13.0 are now End Of Life (EOL) and are vulnerable. Customers are recommended to upgrade their appliances to one of the supported versions that address the vulnerabilities.
Additional Note: Secure Private Access on-prem or Secure Private Access Hybrid deployments using NetScaler instances are also affected by the vulnerabilities. Customers need to upgrade these NetScaler instances to the recommended NetScaler builds to address the vulnerabilities.
This bulletin only applies to customer-managed NetScaler ADC and NetScaler Gateway. Cloud Software Group upgrades the Citrix-managed cloud services and Citrix-managed Adaptive Authentication with the necessary software updates.
Disclaimer
The information on this page is being provided to you on an «AS IS» and «AS-AVAILABLE» basis. The issues described on this page may or may not impact your system(s). Cloud Software Group, Inc. and its subsidiaries (collectively, «Cloud SG») make no representations, warranties, or guarantees as to the information contained herein. ANY AND ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY, NON-INFRINGEMENT AND FITNESS FOR A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. BY ACCESSING THIS PAGE, YOU ACKNOWLEDGE THAT CLOUD SG SHALL IN NO EVENT BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES THAT ARISE OUT OF YOUR USE OR FAILURE TO USE THE INFORMATION CONTAINED HEREIN. Cloud SG reserves the right to change or update the information on this page at any time. We accordingly recommend that you always view the latest version of this page. The information contained herein is being provided to you under the terms of your applicable customer agreement with Cloud SG, and may be used only for the purposes contemplated by such agreement. If you do not have such an agreement with Cloud SG, this information is provided under the cloud.com Terms of Use, and may be used only for the purposes contemplated by such Terms of Use.
Details
NetScaler ADC and NetScaler Gateway contain the vulnerabilities mentioned below:
CVE ID
Description
Pre-conditions
CWE
CVSSv4
CVE-2025-5349
Improper access control on the NetScaler Management Interface
Access to NSIP, Cluster Management IP or local GSLB Site IP
CWE-284: Improper Access Control
CVSS v4.0 Base Score: 8.7(CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L)
CVE-2025-5777
Insufficient input validation leading to memory overread
NetScaler must be configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server
CWE-125: Out-of-bounds Read
CVSS v4.0 Base Score: 9.3(CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L)
What Customers Should Do
Cloud Software Group strongly urges affected customers of NetScaler ADC and NetScaler Gateway to install the relevant updated versions as soon as possible.
NetScaler ADC and NetScaler Gateway 14.1-43.56 and later releases
NetScaler ADC and NetScaler Gateway 13.1-58.32 and later releases of 13.1
NetScaler ADC 13.1-FIPS and 13.1-NDcPP 13.1-37.235 and later releases of 13.1-FIPS and 13.1-NDcPP
NetScaler ADC 12.1-FIPS 12.1-55.328 and later releases of 12.1-FIPS
Additionally, we recommend running the following commands to terminate all active ICA and PCoIP sessions after all NetScaler appliances in the HA pair or cluster have been upgraded to the fixed builds.:
kill icaconnection -all
kill pcoipConnection -all
Please ensure that the formatting remains intact as you copy and paste these commands.
Note: NetScaler ADC and NetScaler Gateway versions 12.1 and 13.0 are now End Of Life (EOL) and no longer supported. Customers are recommended to upgrade their appliances to one of the supported versions that address the vulnerabilities.
