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TI-2026-25771 Aliases CVE-2026-33371GHSA-mc6f-xmmw-r6pv

An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1.

Priority LOW 20CWE-611Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-611 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00244 15th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*10.0.0 to before 10.1.16VulnerableSynacor
  • cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:* Versions 10.0.0 to before 10.1.16 Vulnerable ·Synacor

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33371
  2. 2026-10-03 Alias added: GHSA-mc6f-xmmw-r6pv

References

Advisory 2

Other 2

  • TI-2024-30554 The postjournal service in Zimbra Collaboration (ZCS) before 8.8.15 Patch 46, 9 before… KEVCVSS 3.1CRITICAL 10.0
  • TI-2022-19841 An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0. KEVCVSS 3.1CRITICAL 9.8
  • TI-2022-17239 Zimbra Collaboration Suite (ZCS) 8.8.15 and 9.0 has mboximport functionality that… KEVCVSS 3.1CRITICAL 9.8
  • TI-2022-10792 Zimbra Collaboration (aka ZCS) 8.8.15 and 9.0 allows an unauthenticated attacker to… KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-06312 Zimbra Collaboration Suite (ZCS) before 8.8.15 Patch 7 allows SSRF when WebEx zimlet is… KEVCVSS 3.1CRITICAL 9.8
  • TI-2019-07076 mailboxd component in Synacor Zimbra Collaboration Suite 8.7.x before 8.7.11p10 has an… KEVCVSS 3.1CRITICAL 9.8
See all 96 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences