CVE-2026-93627 Details
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 An attacker who knows the meeting UID and organizer address can supply a non-outdated sequence number to move the recipient's meeting to Trash or replace its details.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.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Oct 28, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories | [email protected] | |
| https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/ | [email protected] |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-290 | Authentication Bypass by Spoofing | [email protected] |
Affected Products
No affected product data is available for this CVE.
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Oct 28, 2026 | CVE Modified | CISA-ADP |
| Oct 23, 2026 | New CVE Received | [email protected] |