Medium 4.3Published Mar 19, 2026

CVE-2026-33371An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1.

Updated under an hour ago (Oct 27, 2026, 1:00 PM ET)

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It affects synacor zimbra_collaboration_suite. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for synacor zimbra_collaboration_suite

Exploited in the last 30 days

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.

CVSS: 4.3 MEDIUM (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Weakness (CWE): CWE-611
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mitre
NVD analysis: Analyzed
Record last updated: Mar 23, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

synacor zimbra_collaboration_suite synacor:zimbra_collaboration_suite	from 10.0.0 before 10.1.16	NVD

References

References

https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories	vendor-advisory
https://wiki.zimbra.com/wiki/Security_Center	release-notes, vendor-advisory
https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy	product
https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.16#Security_Fixes	release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.