Zimbra Stored XSS in Share Notification Allows Account Takeover

Zimbra Modern contains a stored XSS vulnerability in its share notification handling.

An unauthenticated sender can forge a share notification. When a signed-in recipient clicks Accept Share, the malicious script executes.

• Attack requires no authentication for the sender.
• Victim must be signed in to Zimbra Modern and click Accept Share.
• Impact: attacker can access mailbox data and act as the victim.