{"id":"CVE-2026-93634","title":"Zimbra Collaboration Suite Cross-Account Authorization Bypass via Forged Shared-File Records","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…","severity":"medium","cvss":4.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","cvssSource":"cna","cwe":["CWE-639"],"vendor":"Zimbra","product":"Zimbra Collaboration Suite","affected":["collaboration_suite <= 10.1.20"],"published":"2026-10-23","updated":"2026-10-23","sourceUpdated":"2026-10-23T13:26:11.070Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-93634","references":[{"url":"https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories"},{"url":"https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/"}],"tags":["cve.org"],"ingestedAt":"2026-10-23T14:28:08.710Z","slug":"CVE-2026-93634","body":"## Overview\n\nA 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.\n\n## Affected\n\n- `collaboration_suite <= 10.1.20`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":24,"depthScoreParts":{"impact":23.7,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}