CVE-2026-93643: critical vulnerability in Zimbra Collaboration Suite (ZCS)
Zimbra Collaboration Suite OnlyOffice Integration Path Traversal Leading to Remote Code Execution via Unauthenticated /downloadas Request
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.8epss 1.0%
When OnlyOffice/Document Editing is available, an unauthenticated remote attacker with access to an existing supported public Briefcase document can abuse unsigned save fields to perform path-traversal writes and execute commands as zimbra.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Zimbra · Zimbra Collaboration Suite (ZCS)Related CVEs — Zimbra Collaboration Suite (ZCS)
In the same product, most dangerous first.
CVE-2026-93641CRITICALZimbra Collaboration Suite Classic Web Client Stored Cross-Site Scripting via Forged Share InvitationEPSS 0.3%CVE-2026-93647CRITICALZimbra Collaboration Suite Classic Web Client Stored Cross-Site Scripting via Crafted Calendar COUNTER Message From AddressEPSS 0.2%CVE-2026-93642CRITICALZimbra Collaboration Suite Modern Web Client Stored Cross-Site Scripting via Forged Share InvitationEPSS 0.2%