Critical Citrix NetScaler auth bypass now leveraged in attacks
BLUF
Active exploitation of a critical Citrix NetScaler auth bypass vulnerability is underway.
NEWS
Threat actors are leveraging CVE-2026-19490 to bypass authentication on Citrix NetScaler appliances, according to intelligence from Previdian. This critical-severity flaw allows attackers to gain unauthorized access without valid credentials as of September 2026.
Why I Care
Unpatched NetScaler instances are at immediate risk of compromise, potentially leading to data theft or full network takeover. This affects any organization relying on Citrix for remote access or application delivery.
Next Steps
Administrators should apply the latest Citrix security patches immediately and verify if their systems are exposed. Security teams should monitor logs for suspicious authentication attempts and isolate affected devices until patched.
Source: BleepingComputer ·