Synacor Zimbra Collaboration Suite (ZCS) Improper Restriction of XML External Entity Reference

Synacor Zimbra Collaboration Suite (ZCS) contains an improper restriction of XML external entity (XXE) vulnerability in the mailboxd component.

Published 12 Sep 2026Updated 12 Sep 20264 sources
CVSS 9.8 ✓ VERIFIED REFERENCE△ CISA KEV

Source timeline

Discovered through CISA Known Exploited VulnerabilitiesView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗