Vulnerabilities / CVE-2026-93634

CVE-2026-93634

Published 2026-10-23 · published (not yet in NVD)

CVE-2026-93634

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

4.3 MEDIUM
CVSS 3.1 · CNA

0.3%
chance of exploitation in the next 30 days (EPSS; higher than 19% of CVEs)

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.

Scores

4.3CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:NCNA

Affected products

Zimbra Zimbra Collaboration Suite: 0 to ≤ 10.1.20

Weakness: CWE-639

2 references (advisories, patches, write-ups)

https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories · vendor-advisory
https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/ · related

Sources: CVE.org, FIRST EPSS. Missing ones did not answer or have no record yet.

Look up another CVE Check your dependencies Scan a website