CVE-2026-93627
MEDIUM
MEDIUM
Priority: 0.01
BB Relevance:
71/100
Published: 2026-10-23
Modified: 2026-10-28
First seen: 2026-10-29
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
Unchanged
C:
None
I:
Low
A:
None
Description
An organizer authentication vulnerability in the email calendar processing of Zimbra Collaboration Suite (ZCS) allows an unauthenticated sender to cancel or modify an existing meeting in a recipient's calendar. Zimbra accepts iCalendar CANCEL and REQUEST components without verifying that the email sender is authorized to act as the supplied organizer. An attacker who knows the meeting UID and organizer address can supply a non-outdated sequence number to move the recipient's meeting to Trash or replace its details. Processing occurs automatically during email delivery without recipient interaction. ZCS 10.1.16 and 10.1.21 are affected.
Weakness Classification (1)
Affected Software (2)
| Vendor | Product | Version |
|---|---|---|
| Zimbra | Zimbra Collaboration Suite | 0 |
| Zimbra | Zimbra Collaboration Suite | 0 |