# Cybercriminals Exploit Citrix NetScaler Vulnerability in Ongoing Attacks

*Published September 7, 2026*
*Source: [https://www.bleepingcomputer.com/news/security/hackers-target-critical-citrix-netscaler-auth-bypass-in-attacks/](https://www.bleepingcomputer.com/news/security/hackers-target-critical-citrix-netscaler-auth-bypass-in-attacks/)*

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## Article

A critical security vulnerability in Citrix NetScaler, identified as CVE-2026-19490, is being actively exploited by cybercriminals. This authentication bypass flaw allows attackers to gain unauthorized access by using valid credentials, significantly reducing the effectiveness of traditional prevention measures once the attackers infiltrate the system. The vulnerability has become a prime target for exploitation, prompting security teams to take immediate action to safeguard their systems.

The Blue Report 2026, which assesses defense capabilities across various techniques, highlights the challenge of maintaining robust security once initial access is achieved by attackers. With 338 million simulations conducted in customer production environments, the report underscores the need for continuous monitoring and adaptive security measures to counteract the sophisticated tactics employed by cybercriminals.

Organizations relying on Citrix NetScaler need to be vigilant in addressing this threat. Ensuring systems are patched and updated, along with implementing comprehensive security strategies, is crucial to mitigating the risk posed by this vulnerability. As attackers continue to leverage such flaws, proactive security measures remain the best defense against potential breaches.