CISA Mandates Federal Agencies Patch Citrix NetScaler Zero-Day (CVE-2026-88779) by October 7

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) added a high-severity zero-day vulnerability in Citrix NetScaler ADC and NetScaler Gateway, tracked as CVE-2026-88779, to its Known Exploited Vulnerabilities (KEV) catalog. Federal agencies are required to apply patches by October 7, 2026, due to active exploitation of this memory overflow vulnerability, which can lead to denial-of-service under specific deployment conditions.