CVE-2026-33371

Published: Mar 20, 2026Updated: Apr 1, 2026 Sources: CVE List NVD BDUCWE-611

4.3MEDIUM

NVD MITRE

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:LConfidentiality

Low

I:NIntegrity

None

A:NAvailability

None

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Weaknesses

CWE-611

Affected Products

synacor

commercial·US

zimbra collaboration suiteOn-premWeb App

Communications / email-server-client

Zimbra Inc.

commercial·US

Zimbra Collaboration SuiteMixed

Communications / email-server-client

and 1 more affected products View all →

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Collection

Initial Access

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References

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

wiki.zimbra.com

https://wiki.zimbra.com/wiki/Security_Center

wiki.zimbra.com

https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy

wiki.zimbra.com

and 2 more references View all →

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