Unauthenticated RCE Chain Found For Microsoft SharePoint CVE-2026-55040 and CVE-2026-63520

<p class="wp-block-paragraph">Security researchers have disclosed a critical exploit chain affecting on-premises Microsoft SharePoint Server that allows unauthenticated attackers to achieve remote code execution (RCE). The chain leverages two distinct vulnerabilities—an authentication bypass and an unsafe .NET type instantiation flaw—to provide full server control without valid credentials.</p>