CISA warns: patch actively exploited SharePoint flaws
🔒 The U.S. Cybersecurity and Infrastructure Security Agency (CISA) warned that attackers are actively exploiting three SharePoint Server vulnerabilities (CVE-2026-32201, CVE-2026-45659, CVE-2026-56164) in Internet-exposed on-premises instances. The flaws enable authentication bypass, remote code execution, and post-exploitation activity including theft of IIS machine keys and persistence to deploy malware. CISA urged administrators to apply Microsoft's patches, verify installation, shorten patch cycles, enable AMSI integration for SharePoint, use Microsoft Defender Antivirus detections, and implement hardening and monitoring measures.
