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TI-2026-69618 Aliases CVE-2026-10631GHSA-7jfc-2g3q-h5mf

Zimbra Collaboration Suite EWS authorization bypass exposes mailboxes

Priority LOW 29CWE-639Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-639.

Summary

Zimbra Collaboration Suite from 10.1.0 before 10.1.20 contains an authorization bypass in the EWS FindItem handler. An authenticated user with EWS enabled can read complete mailbox items, including raw MIME and attachments, from arbitrary local accounts without a share or delegation grant, related to CWE-639.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

An authorization bypass in the EWS FindItem handler of Zimbra Collaboration Suite 10.1.0 through 10.1.19 allows an authenticated user with EWS enabled to read complete mailbox items, including raw MIME and attachments, from arbitrary local accounts without a share or delegation grant.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00287 21st percentileScored 2026-11-07
Fix Fixed Zimbra Collaboration Suite (Zimbra): 10.1.20

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ZimbraZimbra Collaboration Suitebefore 10.1.2010.1.20Patch availableCNA
  • Zimbra Collaboration Suite VendorZimbra Affected before 10.1.20 Fixed in 10.1.20 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*——Synacor
  • cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:* Versions — — ·Synacor

Remediation

Upgrade Zimbra Collaboration Suite to version 10.1.20. The sources do not list a vendor advisory for this fix.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA Zimbra Collaboration Suite (Zimbra) Fixed in 10.1.20

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Zimbra Collaboration Suite 10.1.20

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2026-69620 Zimbra Collaboration Suite flaw lets accounts grant mailbox accessPriority LOW 30
    • TI-2026-69621 Sieve notify action bypasses mail forwarding restriction in ZimbraPriority LOW 29
    Show all 3 records →

Timeline

  1. 2026-10-08 Threatist record created from CVE-2026-10631
  2. 2026-10-08 CISA SSVC decision points changed
  3. 2026-10-09 Alias added: GHSA-7jfc-2g3q-h5mf
  4. 2026-10-09 Priority changed: MEDIUM → LOW

References

Advisory 1

  • TI-2026-51660 OS command injection in Zimbra Collaboration KEVCVSS 3.1HIGH 8.9
  • TI-2025-40820 Cross-site scripting in Zimbra Collaboration KEVCVSS 3.1HIGH 7.2
  • TI-2024-18266 An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0. KEVCVSS 3.1MEDIUM 6.1
  • TI-2024-30553 An issue was discovered in Zimbra Collaboration (ZCS) 10.1.x before 10.1.1, 10.0.x before… CVSS 3.1HIGH 8.8
  • TI-2022-13998 Zimbra Collaboration Open Source 8.8.15 does not encrypt the initial-login randomly… CVSS 3.1CRITICAL 9.8
  • TI-2026-63080 Path traversal in Zimbra Collaboration Suite CVSS 3.1CRITICAL 9.8
See all 94 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences