Buffer overflow in Citrix Netscaler ADC and Citrix NetScaler Gateway - CVE-2026-8655
Published: June 30, 2026
Vulnerability identifier: #VU135998
CSH Severity: Medium
CVSS v4: 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]
CVE-ID: CVE-2026-8655
CWE-ID: CWE-119
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper restriction of operations within the bounds of a memory buffer in the Oracle load balancing, DNS proxy, or DNS recursive resolver functionality when handling network requests. A remote attacker can send a specially crafted request to cause a denial of service.
NetScaler ADC must be configured as an Oracle load balancer, a DNS proxy, or a DNS recursive resolver deployment.
Affected software
Citrix Netscaler ADC
Citrix NetScaler Gateway
Citrix NetScaler Gateway
How to mitigate CVE-2026-8655
Install security update from vendor's website.
Citrix Netscaler ADC - addressed in versions 13.1-63.18, 14.1-72.61
Citrix NetScaler Gateway - addressed in versions 13.1-63.18, 14.1-72.61
Citrix NetScaler Gateway - addressed in versions 13.1-63.18, 14.1-72.61