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TI-2026-51661 Aliases CVE-2026-73571GHSA-p856-mgqw-j9rq

Incorrect authorization in Zimbra Collaboration

Priority LOW 20CWE-863Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-863.

Summary

An authorization bypass vulnerability exists in Zimbra Collaboration (ZCS) before 10.1.17 due to improper authorization validation in delegated email sending functionality. An authenticated attacker can send specially crafted SOAP requests to impersonate another user and send emails without possessing the required delegation or send-as permissions. This occurs in the SaveDraftRequest SOAP handler.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00258 17th percentileScored 2026-11-07
Fix Fixed Collaboration (Zimbra): 10.1.17

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
ZimbraCollaborationbefore 10.1.1710.1.17Patch availableCNA
  • Collaboration VendorZimbra Affected before 10.1.17 Fixed in 10.1.17 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*before 10.1.17VulnerableSynacor
  • cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:* Versions before 10.1.17 Vulnerable ·Synacor

Remediation

  • Fix · CNA Collaboration (Zimbra) Fixed in 10.1.17

Fixed in the same release

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

  • Release ·

    Zimbra Collaboration 10.1.17

    6 records Highest priority Priority LOW 6 LOW

    Other records, highest priority first

    • TI-2026-51664 In Zimbra Collaboration before 10.1.17, a local file inclusion (LFI) vulnerability exists…Priority LOW 35
    • TI-2026-51666 In Zimbra Collaboration (ZCS) before 10.1.17, weak cryptographic key generation…Priority LOW 29
    • TI-2026-51663 Path traversal in Zimbra CollaborationPriority LOW 29
    Show all 6 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-73571
  2. 2026-10-03 Alias added: GHSA-p856-mgqw-j9rq

References

Advisory 2

  • 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