Critical

New NetScaler Zero-Day Exploited in Targeted Attacks Can Knock SAML Deployments Offline

The Hacker News

October 5, 2026 at 6:40 AM

Actively Exploited

Overview

Citrix has announced security updates for a serious vulnerability in its NetScaler ADC and Citrix NetScaler Gateway products, identified as CVE-2026-88779. This memory overflow flaw has a CVSS score of 8.7, indicating a high level of severity. Attackers are actively exploiting this zero-day vulnerability in targeted attacks, which can disrupt SAML (Security Assertion Markup Language) deployments, potentially knocking them offline. Users of these systems should prioritize applying the available security updates to mitigate the risk of exploitation. This incident underscores the need for organizations to stay vigilant about their cybersecurity practices, especially when using widely deployed network infrastructure.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: Citrix NetScaler ADC, Citrix NetScaler Gateway
Action Required: Citrix has released security updates to address CVE-2026-88779.
Timeline: Newly disclosed

Original Article Summary

Citrix has released security updates for a high-severity security flaw in NetScaler ADC and Citrix NetScaler Gateway that has been exploited as part of targeted zero-day attacks. The vulnerability, tracked as CVE-2026-88779, carries a CVSS score of 8.7 out of 10.0. "CVE-2026-88779 is a memory overflow vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway that can lead to

Impact

Citrix NetScaler ADC, Citrix NetScaler Gateway

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Newly disclosed

Remediation

Citrix has released security updates to address CVE-2026-88779. Users are advised to apply these updates promptly to protect against potential exploitation.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Zero-day, Vulnerability.

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