CVE-2026-78509

A heap-based buffer overflow vulnerability in Microsoft Office Outlook enables unauthorized attackers to execute arbitrary code remotely, posing a critical risk to systems using this application. Organizations relying on Microsoft Office, particularly those with Outlook deployed, should prioritize patching this vulnerability to mitigate potential exploitation and safeguard sensitive data. Immediate action is essential due to the high severity rating of 9.8 on the CVSS scale.