zero-click exfiltration

Zero-click exfiltration refers to a class of security vulnerability where an attacker can extract sensitive data from a target system without any user interaction, such as clicking a link or opening a file. On WindowsForum.com, discussions highlight a notable example in Microsoft Excel, tracked as CVE-2026-26144, a cross-site scripting flaw that can be weaponized for zero-click data theft when combined with agentic features like Microsoft's Copilot Agent. This technique poses significant risks in enterprise environments, especially as systems transition from Windows 10 to Windows 11, leaving outdated platforms exposed. The tag covers threats that bypass traditional user-aware defenses, emphasizing the need for proactive patching and security updates.