CVE-2026-33371
Medium
Description
An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. An XML External Entity (XXE) vulnerability exists in the Zimbra Exchange Web Services (EWS) SOAP interface due to improper handling of XML input. An authenticated attacker can submit crafted XML data that is processed by an XML parser with external entity resolution enabled. Successful exploitation may allow disclosure of sensitive local files from the server.
SeverityMedium
CVSS4.3
Exploit probability—
Product
Synacor Zimbra Collaboration Suite
PublishedMar 20, 2026
First seenMar 20, 2026
Weakness typeCWE-611XML external entity (XXE)
How to fix
Update
- synacor zimbra_collaboration_suite10.1.16 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| synacor zimbra_collaboration_suite | 10.0.0 ≤ v < 10.1.16 | 10.1.16 |
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