US, Australia warn of latest Citrix vulnerability after NetScaler advisory

A newly observed high-severity vulnerability (CVE-2026-88779; CVSS 8.7) in Citrix NetScaler ADC/Gateway appliances is being actively exploited to cause denials of service, with Citrix and CISA issuing advisories and urgent patching/triage orders; the issue is related to, but distinct from, recent CVE-2026-88771/88772 exploitation, and attacks have been reported across government, financial, technology, education, and legal sectors.