Citrix Issues Critical Security Advisory for NetScaler ADC and Gateway – Immediate Action Required
A vulnerability has been discovered in NetScaler ADC (formerly Citrix ADC) and NetScaler Gateway (formerly Citrix Gateway) CTX694938
On August 26, 2025, Citrix released a security bulletin (CTX694938) addressing three critical vulnerabilities impacting NetScaler ADC and NetScaler Gateway appliances.
These vulnerabilities — CVE-2025-7775, CVE-2025-7776, and CVE-2025-8424 — pose severe security risks, including Remote Code Execution (RCE), Denial of Service (DoS), and improper access control. Citrix has confirmed that active exploitation of CVE-2025-7775 is occurring in the wild, making immediate remediation essential.
What’s the Risk?
- CVE-2025-7775 (Critical): Memory overflow vulnerability that can lead to Remote Code Execution or Denial of Service. This flaw is actively exploited.
- CVE-2025-7776: Allows Denial of Service under certain conditions.
- CVE-2025-8424: Improper access control vulnerability that could allow unauthorized access.
Affected products include NetScaler ADC and NetScaler Gateway in specific configurations. If left unpatched, attackers could gain control of systems, disrupt services, or access sensitive data.
Who is Affected?
Organizations using NetScaler ADC or NetScaler Gateway appliances, particularly those running:
- Versions 13.1, 14.1, 13.1-FIPS, and NDcPP builds.
Recommended Actions
Citrix strongly advises:
- Apply the latest security updates immediately as outlined in Citrix KB CTX694938.
- Review your environment for signs of compromise.
- Restrict access to management interfaces and enforce strong authentication.
- Monitor Citrix advisories and threat intelligence for updates.