CISA Adds Exploited SharePoint RCE ZeroDay CVE202658644 to KEV

The US Cybersecurity and Infrastructure Security Agency CISA on Thursday added a newly patched security flaw impacting Microsoft SharePoint Server to its Known Exploited Vulnerabilities KEV catalog requiring Federal Civilian Executive Branch FCEB agencies to apply the fixes by July 19 2026 The vulnerability in question is CVE202658644 CVSS score 98 a critical deserialization