CVE-2026-93647 — Zimbra Collaboration Suite Classic Web Client Stored Cross-Site Scripting via Crafted Calendar COUNTER Message From A…

CVE-2026-93647

Zimbra Collaboration Suite Classic Web Client Stored Cross-Site Scripting via Crafted Calendar COUNTER Message From Address PUBLISHED

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
Zimbra / Zimbra Collaboration Suite (ZCS)	affected 0 before 10.1.21

CWE

CWE-79

References

https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.