CVE-2026-93629 (GCVE-0-2026-93629)

Vulnerability from cvelistv5 – Published: 2026-10-23 13:19 – Updated: 2026-10-23 13:19
VLAI
Title
Zimbra Collaboration Suite Calendar Processing Authentication Bypass via Forged iCalendar REQUEST Organizer Identity
Summary
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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-290 - Authentication bypass by spoofing
Assigner
rapid7 CNA under the mitre root
CNA scorecard B 76/100 over 81 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Zimbra Zimbra Collaboration Suite Affected: 0 , ≤ 10.1.21 (semver)
guessed Create a notification for this product.
Date Public
2026-10-23 12:47
Credits
Jonah Burgess (CryptoCat), Senior Security Researcher, Rapid7
Show details on NVD website
To clipboard 

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