Citrix hat für NetScaler die CVE-2026-107406 aktualisiert (Base Score: 9.5). Die Severity wurde als «Hoch» eingestuft. Es sind alle NetScaler mit SAML in Version 13.1 und 14.1 betroffen.
Hinweis: NetScaler mit einem AXACOM NetScaler Update Service, AXACOM Managed Kunden oder ROX NetScaler Kunden werden noch heute oder zum vereinbarten Wartungsfenster aktualisiert.
Weitere Infos: Severity – High
Description of Problem
A vulnerability has been discovered in Citrix NetScaler ADC (formerly Citrix ADC) and Citrix NetScaler Gateway (formerly Citrix Gateway). Refer below for further details.
Affected Versions:
The following supported versions of Citrix NetScaler ADC and Citrix NetScaler Gateway are affected by the vulnerability if they meet the following conditions: NetScaler ADC or NetScaler Gateway must be configured as a SAML SP or SAML IdP, subject to the following version-specific requirements:
For the following versions: Applicable only when configured as a SAML IdP:
NetScaler ADC and NetScaler Gateway between 14.1-73.37 and 14.1-73.41, inclusive
NetScaler ADC 14.1-FIPS between 14.1-73.37 FIPS and 14.1-73.41 FIPS, inclusive
NetScaler ADC and NetScaler Gateway between 13.1-64.23 and 13.1-64.28, inclusive
NetScaler ADC 13.1-FIPS between 13.1-NDcPP 13.1-37.279 and 13.1- 37.282, inclusive
For the following versions: Applicable only when configured as a SAML SP or SAML IdP:
NetScaler ADC and NetScaler Gateway before 14.1-73.37
NetScaler ADC 14.1-FIPS before 14.1-73.37 FIPS
NetScaler ADC and NetScaler Gateway before 13.1-64.23
NetScaler ADC 13.1-FIPS before 13.1-NDcPP 13.1-37.279
Additional Note: Secure Private Access Hybrid deployments using NetScaler instances are also affected by the vulnerability. Customers need to upgrade these NetScaler instances to the recommended NetScaler versions to address the vulnerability.
This bulletin only applies to customer-managed Citrix NetScaler ADC (“NetScaler ADC”) and Citrix NetScaler Gateway (“NetScaler Gateway”). Cloud Software Group upgrades the Citrix-managed cloud services and Citrix-managed Adaptive Authentication with the necessary software updates.
Details
Citrix NetScaler ADC and Citrix NetScaler Gateway are affected by the vulnerability identified below
CVE-ID
Description
Pre-conditions
CWE
CVSSv4
CVE-2026-107406
Memory overflow vulnerability leading to Remote Code Execution or Denial of Service
NetScaler ADC or NetScaler Gateway must be configured as a SAML SP or SAML IdP, subject to the following version-specific requirements: For the following versions: Applicable only when configured as a SAML IdP:NetScaler ADC and NetScaler Gateway between 14.1-73.37 and 14.1-73.41, inclusiveNetScaler ADC 14.1-FIPS between 14.1-73.37 FIPS and 14.1-73.41 FIPS, inclusiveNetScaler ADC and NetScaler Gateway between 13.1-64.23 and 13.1-64.28, inclusiveNetScaler ADC 13.1-FIPS between 13.1-NDcPP 13.1-37.279 and 13.1- 37.282, inclusive For the following versions: Applicable only when configured as a SAML SP or SAML IdP:NetScaler ADC and NetScaler Gateway before 14.1-73.37 NetScaler ADC 14.1-FIPS before 14.1-73.37 FIPS NetScaler ADC and NetScaler Gateway before 13.1-64.23NetScaler ADC 13.1-FIPS before13.1-NDcPP 13.1-37.279
CWE-119 – Improper Restriction of Operations within the Bounds of a Memory Buffer
CVSS v4.0 Base Score: 9.5 (CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:L)
What Customers Should Do
Cloud Software Group strongly urges affected customers of NetScaler ADC and NetScaler Gateway to install the following updated versions as soon as possible:
Citrix NetScaler ADC and Citrix NetScaler Gateway 14.1-73.46 and later releases
Citrix NetScaler ADC and Citrix NetScaler Gateway 13.1-64.29 and later releases of 13.1
Citrix NetScaler ADC 14.1-FIPS 14.1-73.46 FIPS and later releases of 14.1-FIPS
Citrix NetScaler ADC 13.1-FIPS and 13.1-NDcPP 13.1.37.283 and later releases of 13.1-FIPS and 13.1-NDcPP
Steps to determine if an appliance meets the CVE preconditions
Instructions:
Customers can determine whether their NetScaler deployment is configured as a SAML identity provider (IdP) or service provider (SP) by checking its configuration for entries matching either of the following:
Appliance is configured as a SAML SP
add authentication samlAction
Appliance is configured as a SAML IdP
add authentication samlIdPProfile
(Note: For version-specific requirements, see the “Affected Versions” section above.)
Citrix hat für NetScaler die CVE-2026-88779 aktualisiert (Base Score: 8.7). Die Severity wurde als «Hoch» eingestuft. Es sind alle NetScaler mit SAML in Version 13.1 und 14.1 betroffen.
Hinweis: NetScaler mit einem AXACOM NetScaler Update Service, AXACOM Managed Kunden oder ROX NetScaler Kunden werden noch heute oder zum vereinbarten Wartungsfenster aktualisiert.
Weitere Infos: Severity – High
Description of Problem
A vulnerability has been discovered in Citrix NetScaler ADC (formerly Citrix ADC) and Citrix NetScaler Gateway (formerly Citrix Gateway). Refer below for further details.
Affected Versions:
The following supported versions of NetScaler are affected by the vulnerability:
Citrix NetScaler ADC and Citrix NetScaler Gateway 14.1 BEFORE 14.1-73.41
Citrix NetScaler ADC and Citrix NetScaler Gateway 13.1 BEFORE 13.1-64.28
Citrix NetScaler ADC FIPS BEFORE 14.1-73.41 FIPS
Citrix NetScaler ADC FIPS and NDcPP BEFORE 13.1-37.282
Additional Note: 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 Citrix NetScaler ADC (“NetScaler ADC”) and Citrix NetScaler Gateway (“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 Holdings, Inc. and its affiliates, including Citrix Systems, Inc. (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. Cloud SG accordingly recommends 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 is affected by the vulnerability described below
CVE-ID
Description
Pre-conditions
CWE
CVSSv4
CVE-2026-88779
Memory overflow vulnerability leading to Denial of Service
NetScaler ADC or NetScaler Gateway must be configured as aSAML SPORSAML IdP
CWE-119 – Improper Restriction of Operations within the Bounds of a Memory Buffer
CVSS v4.0 Base Score: 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
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 14.1-73.41 and later releases
NetScaler ADC and NetScaler Gateway 13.1-64.28 and later releases of 13.1
NetScaler ADC 14.1-FIPS 14.1-73.41 FIPS and later releases of 14.1-FIPS
NetScaler ADC 13.1-FIPS and 13.1-NDcPP 13.1-37.282 and later releases of 13.1-FIPS and 13.1-NDcPP
Steps to determine if an appliance meets the CVE preconditions
Instructions:
Customers can determine whether their NetScaler deployment meets the precondition by inspecting their NetScaler configuration for entries matching either of the following:
Appliance is configured as a SAML SP add authentication samlAction
OR
Appliance is configured as a SAML IdP add authentication samlIdPProfile
Ein kurzes Heads-up zu den aktuellen NetScaler Security Updates, konkret zum CVE-2026-88778: Wie beim Review des aktuellen Citrix Security Bulletins klar wurde, bietet ein reines Firmware-Update noch keinen vollständigen Schutz.
Um die Appliances abzusichern, muss bei allen NetScalern zwingend ein TCP-Parameter angepasst werden.
Aktuellen Status prüfen:
show ns tcpparam | grep "Enhanced ISN Generation"
Fix aktivieren:
set ns tcpparam -enhancedISNgeneration ENABLED
(Vergesst nicht, die Config im Anschluss mit save config zu speichern!)
Glücklicherweise gibt es zu diesem CVE-2026-88778 noch keine Meldungen von erfolgreich durchgeführten Attacken. Trotzdem empfiehlt die AXACOM AG dieses Hardening durchzuführen!
Bei unseren ROX Managed- und Updateservice Kunden werden wir das Hardening im Rahmen des nächsten Wartungsfensters automatisch verteilen.
Bei Fragen oder allfälliger benötigter Hilfestellung, stehen wir euch über euer AXACOM Support Portal bereit.
Citrix hat für NetScaler 2 neue CVEs (Base Score: 9.3) veröffentlicht. Die Severity wurde als «Kritisch» eingestuft. Es sind alle NetScaler mit AAA und Gateway in Version 13.1 und 14.1 betroffen.
Multiple 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:
NetScaler ADC and NetScaler Gateway 14.1 BEFORE 14.1-73.32
NetScaler ADC and NetScaler Gateway 13.1 BEFORE 13.1-63.21
NetScaler ADC FIPS BEFORE 14.1-73.32 FIPS
NetScaler ADC FIPS and NDcPP BEFORE 13.1-37.277
Additional Note: 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.
Summary:
NetScaler ADC and NetScaler Gateway are affected by the vulnerabilities mentioned below
CVE-ID
Description
Pre-conditions
CWE
CVSSv4
CVE-2026-19489
Memory overflow vulnerability leading to unpredictable behavior or Denial of Service
SIP ALG(Session Initiation Protocol Application Layer Gateway) should be enabled on a Large Scale NAT (LSN) group configuration.
CWE-119 – Improper Restriction of Operations within the Bounds of a Memory Buffer
CVSS v4.0 Base Score: 8.8(CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:L)
CVE-2026-19490
Authentication bypass using an alternate path
The appliance must be configured as a Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or an AAA virtual server, subject to the following version-specific requirements:14.1-43.56 or later: Applicable only when configured with a SAML action.
14.1-43.55 or earlier: Applicable when configured with Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy ) or AAA vserver
13.1-61.28 or later: Applicable only when configured with a SAML action.
13.1-61.27 or earlier: Applicable when configured with Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or AAA vserver
13.1 FIPS: Applicable when configured with Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or AAA vserver.
CWE-288: Authentication Bypass Using an Alternate Path
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 14.1-73.32 and later releases
NetScaler ADC and NetScaler Gateway 13.1-63.21 and later releases of 13.1
NetScaler ADC 14.1-FIPS 14.1-73.32 FIPS and later releases of 14.1-FIPS
NetScaler ADC 13.1-FIPS and 13.1-NDcPP 13.1-37.277 and later releases of 13.1-FIPS and 13.1-NDcPP
Steps to determine if an appliance meets the CVE preconditions
For CVE-2026-19489:
Customers can determine if the appliance meets the precondition by inspecting their NetScaler configuration for the specified string:
«add lsn group.*sipalg.*»
For CVE-2026-19490:
Customers can determine if the appliance meets the precondition by inspecting their NetScaler configuration for the specified string:
An issue has been identified in the XenServer management API SDK that may allow an attacker on the management network who is able to intercept specific HTTPS requests within a higher-level operation to be able to act with the privileges of the intercepted administrator. This issue affects the XenCenter management agent together with third-party PowerShell and C# SDK clients.
This issue has the following identifier:
CVE-2026-42491
Affected Versions
This issue affects XenCenter versions before 2026.4.0 and, for PowerShell and C# clients only, SDK versions before 26.15.0. As the issue is in the client-side (XenCenter and SDK) code, it is independent of the version of XenServer that is in use.
