All vulnerabilities
CVE-2026-93634

Zimbra Collaboration Suite Cross-Account Authorization Bypass via Forged Shared-File Records

Zimbra Zimbra Collaboration SuiteApplications & CMS
CVSS
4.3Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)No scoreNo FIRST EPSS score in this snapshot yet
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
Published23 Oct 2026Updated 23 Oct 2026CVE List

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Description

A cross-account authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to insert forged shared-file records into another user's mailbox through FileSharedWithMeRequest. The request bypasses delegated-account authorization and accepts attacker-selected file metadata, owner identifiers and declared sizes without validating a corresponding document share. An attacker can plant entries attributed to another real local account without that account sharing a document. No victim interaction is required. ZCS 10.1.16 and 10.1.20 are affected.

Text from CVE List

Affected versions 1

  • Zimbra Collaboration Suiteaffected: all versions through 10.1.20CVE List

References 2