Zimbra Collaboration Suite Calendar Processing Authentication Bypass via Forged iCalendar REQUEST Organizer Identity
Impact
An organizer authentication vulnerability in Zimbra Collaboration Suite (ZCS) allows an unauthenticated email sender to insert calendar invitations attributed to another user. The email delivery path permits external invitations but does not verify that the message sender is authorized to use the iCalendar ORGANIZER identity. When automatic invitation insertion is enabled, a crafted REQUEST component creates an event containing attacker-selected meeting details and reminders under a forged organizer without recipient interaction. No corresponding event is created in the claimed organizer's…
Source excerpt · rapid7Affected packages
Affected products
Vendor version evidence. Product records are separate from automatic dependency matching.
Zimbra · Zimbra Collaboration Suite
Other versions: unaffected
| Version / range | Source status |
|---|---|
| 0 through 10.1.21 (inclusive) | affected |
Original source description
An organizer authentication vulnerability in Zimbra Collaboration Suite (ZCS) allows an unauthenticated email sender to insert calendar invitations attributed to another user. The email delivery path permits external invitations but does not verify that the message sender is authorized to use the iCalendar ORGANIZER identity. When automatic invitation insertion is enabled, a crafted REQUEST component creates an event containing attacker-selected meeting details and reminders under a forged organizer without recipient interaction. No corresponding event is created in the claimed organizer's calendar. ZCS 10.1.16 and 10.1.21 are affected.