ACTIVELY EXPLOITED VULNERABILITIES CVE-2026-8452 — Citrix NetScaler ADC & Gateway (CVSS 8.8): Memory overflow vulnerability added to CISA KEV on August 26. FCEB agencies must patch by August 29, 2026. Actively exploited in the wild. CVE-2026-55040 + CVE-2026-63520 — Microsoft SharePoint RCE Chain: JWT token authentication bypass (CVE-2026-55040) chained with Business Connectivity Services RCE (CVE-2026-63520). Public PoCs released; active exploitation began within 24 hours. C