Microsoft Exchange Zero-Day Under Attack, No Patch Available

The active exploitation of the Microsoft Exchange zero-day vulnerability CVE-2026-42897 highlights the urgent need for organizations to prioritize cybersecurity updates. This flaw, which enables attackers to compromise Outlook Web Access mailboxes, underscores the growing sophistication of cyber threats targeting enterprise communication systems.

• A zero-day vulnerability is actively being exploited, increasing risk for organizations.
• The flaw allows attackers to compromise Outlook Web Access mailboxes via cross-site scripting.
• Organizations should monitor for updates and implement security measures to mitigate potential breaches.