NetScaler ADC and NetScaler Gateway Security Bulletin for CVE-2025-7775, CVE-2025-7776 and CVE-2025-8424 Article Id : CTX694938 Last Modified Date : 08-26-2025 12:11 Created Date : 08-26-2025 11:40 Article Record Type : Security Bulletin Summary Severity - Critical Description of Problem

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 14.1-47.48
NetScaler ADC and NetScaler Gateway 13.1 BEFORE 13.1-59.22
NetScaler ADC 13.1-FIPS and NDcPP BEFORE 13.1-37.241-FIPS and NDcPP
NetScaler ADC 12.1-FIPS and NDcPP BEFORE 12.1-55.330-FIPS and NDcPP

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-2025-7775

Memory overflow vulnerability leading to Remote Code Execution and/or Denial of Service

NetScaler must be configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server

(OR)

NetScaler ADC and NetScaler Gateway 13.1, 14.1, 13.1-FIPS and NDcPP: LB virtual servers of type (HTTP, SSL or HTTP_QUIC) bound with IPv6 services or servicegroups bound with IPv6 servers

(OR)

NetScaler ADC and NetScaler Gateway 13.1, 14.1, 13.1-FIPS and NDcPP: LB virtual servers of type (HTTP, SSL or HTTP_QUIC) bound with DBS IPv6 services or servicegroups bound with IPv6 DBS servers

(OR)

CR virtual server with type HDX

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)

CVE-2025-7776

Memory overflow vulnerability leading to unpredictable or erroneous behavior and Denial of Service

NetScaler must be configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) with PCoIP Profile bounded to it

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-2025-8424

Improper access control on the NetScaler Management Interface

Access to NSIP, Cluster Management IP or local GSLB Site IP or SNIP with Management Access

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) What Customers Should Do

Exploits of CVE-2025-7775 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 14.1-47.48 and later releases
NetScaler ADC and NetScaler Gateway 13.1-59.22 and later releases of 13.1
NetScaler ADC 13.1-FIPS and 13.1-NDcPP 13.1-37.241 and later releases of 13.1-FIPS and 13.1-NDcPP
NetScaler ADC 12.1-FIPS and 12.1-NDcPP 12.1-55.330 and later releases of 12.1-FIPS and 12.1-NDcPP

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.

CVE-2025-7775:

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)

add vpn vserver .*

LB vserver of Type HTTP_QUIC|SSL|HTTP bound with IPv6 services or servicegroups bound with IPv6 servers:

enable ns feature lb.*

add serviceGroup .* (HTTP_QUIC|SSL|HTTP) .*

add server .* <IPv6>

bind servicegroup <servicegroup name> <IPv6 server> .*

add lb vserver .* (HTTP_QUIC|SSL|HTTP) .*

bind lb vserver .* <ipv6 servicegroup name>

LB vserver of Type HTTP_QUIC|SSL|HTTP bound with DBS IPv6 services or servicegroups bound with IPv6 DBS servers:

enable ns feature lb.*

add serviceGroup .* (HTTP_QUIC | SSL | HTTP) .*

add server .* <domain> -queryType AAAA

add service .* <IPv6 DBS server >

bind servicegroup <servicegroup name> <IPv6 DBS server> .*

add lb vserver .* (HTTP_QUIC | SSL | HTTP) .*

bind lb vserver .* <ipv6 servicegroup name>

CR vserver with type HDX:

add cr vserver .* HDX .*

CVE-2025-7776:

Customers can determine if they have an appliance configured by inspecting their ns.conf file for the specified strings

A Gateway (VPN vserver) with with PCoIP Profile bounded to it

add vpn vserver .* -pcoipVserverProfileName .*

Workarounds/ Mitigating Factors

None

Acknowledgement

Cloud Software Group thanks Jimi Sebree of Horizon3.ai, Jonathan Hetzer, of Schramm & Partnerfor and François Hämmerli for working with us to protect Citrix customers.

Reference: https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX694938