CVE-2026-93647
CRITICAL
NVD
CVSS Score
9.3
Severity
CRITICAL
Published
Sep 25, 2026
Vendor
unknown
Description
An unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address. Selecting the message in Zimbra Classic triggers stored XSS, allowing the attacker to access mailbox data and act as the victim.