CISA Warns of Microsoft Defender 0-Day Vulnerabilities Exploited in Attacks

**CISA added two critical Microsoft Defender vulnerabilities (CVE-2026-45498 — DoS, and CVE-2026-41091 — symlink-based local privilege escalation) to its KEV catalog on May 20, 2026, citing evidence of active exploitation and requiring remediation by June 3, 2026 under BOD 22-01; organizations are urged to apply patches and mitigations immediately to prevent defense bypass and potential escalations.**