MSP cybersecurity news digest, March 23, 2026

This report summarizes recent high‑impact cyber incidents: Interlock ransomware exploited a zero‑day deserialization flaw in Cisco Secure Firewall Management Center allowing unauthenticated remote code execution as root; a critical ScreenConnect cryptographic verification flaw (CVE‑2026‑3564) risks unauthorized access; Marquis and Navia disclosed large breaches exposing hundreds of thousands to millions of records; and a patched Microsoft SharePoint vulnerability (CVE‑2026‑49704) is being exploited in the wild — underscoring elevated risk to centralized management platforms, remote support tools, and third‑party data aggregators.