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) :
Microsoft is investigating two reported zero-day vulnerabilities affecting Microsoft Exchange Server 2013, 2016, and 2019. The first vulnerability, identified as CVE-2022-41040, is a Server-Side Request Forgery (SSRF) vulnerability, while the second, identified as CVE-2022-41082, allows remote code execution (RCE) when PowerShell is accessible to the attacker.
What Customers Should Do
To protect your on-prem Exchange you can bind a responder policy on the Citrix ADC contentswitch handling all the Exchange related traffic:
Vulnerabilities have been discovered in Citrix Application Delivery Management (Citrix ADM) that, if exploited, could result in the following security issues:
Corruption of the system by a remote, unauthenticated user. The impact of this can include the reset of the administrator password at the next device reboot, allowing an attacker with ssh access to connect with the default administrator credentials after the device has rebooted.
Temporary disruption of the ADM license service. The impact of this includes preventing new licenses from being issued or renewed by Citrix ADM.
CVE-ID
Description
CWE
Pre-conditions
CVE-2022-27511
Corruption of the system by a remote, unauthenticated user potentially leading to the reset of the administrator password
CWE-284: Improper Access Control
Access to ADM IP
CVE-2022-27512
Temporary disruption of the ADM license service
CWE-664: Improper Control of a Resource Through its Lifetime
Access to ADM IP
Da der ADM Zugangsdaten & Zugriff auf die konfigurierten Instanzen hat, wird empfohlen die Sicherheitslücke rasch zu schliessen in dem die ADM Instanz auf eine der folgenden Versionen aktualisiert wird:
Citrix ADM 13.1-21.53 and later versions of 13.1
Citrix ADM 13.0-85.19 and later versions of 13.0
Als Mitigation kann versucht werden die ADM Management IP über eine Firewall zu sperren.
Normalerweise ist das ADM nur von intern zugänglich wodurch das Risiko einer Ausnutzung der Schwachstelle relativ klein ist. Ein Angreifer müsste bereits Zugang zum internen Netz haben. Wie die Schwachstelle ausgenutzt werden kann ist bisher unbekannt.
Für detaillierte Informationen und weitere Schritte, folgen Sie bitte den Informationen im Original Citrix Artikel. Gerne unterstützen wir Sie bei bedarf bei dem Update.
