CVE-2026-93628

An attendee authentication vulnerability in the email calendar processing of Zimbra Collaboration Suite ZCS allows an unauthenticated sender to forge another attendee's response to an existing meeting. Zimbra passes a null sender identity when processing iCalendar REPLY components, causing the...

CVE-2026-93628

The Zimbra Collaboration Suite (ZCS) version 10.1.16 and 10.1.21 are vulnerable to an authentication bypass in the email calendar processing. The root cause is that the system passes a null sender identity when processing iCalendar REPLY components, which leads to the attendee authorization filte...

EUVD-2026-108964

An attendee authentication vulnerability in the email calendar processing of Zimbra Collaboration Suite ZCS allows an unauthenticated sender to forge another attendee's response to an existing meeting. Zimbra passes a null sender identity when processing iCalendar REPLY components, causing the...