CVE-2026-93634
MEDIUM severity · CVSS 4.3 · Authorization bypass
4.3CVSS MEDIUM
Summary
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.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredLow
User interactionNone
Confidentiality impactNone
Integrity impactLow
Availability impactNone
Exploit probability (EPSS)0%
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Affected products we track (1)
Recommendation
Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.