CVE-2026-73571

CVE Enrichment

CVSS: 4.3 MEDIUM
EPSS: 0.26%
EPSS Percentile: 16.35%
CISA KEV: Not listed

Description

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.

Technical Details

CVSS Version: 3.1
CNA / NVD Source: cve@mitre.org
Published: 13-Aug-2026 23:19
Last Modified: 28-Aug-2026 20:58
EPSS Date: 2026-10-16
CWE: CWE-863

CVSS Vector


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

Affected Products / Versions

synacor / zimbra_collaboration_suite
Version / affected range: * · before (exclusive) 10.1.17
cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*

References

Last enrichment sync: 17-Oct-2026 10:58
Sources: NVD · FIRST EPSS · CISA KEV
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Reported Context (1)

direct mailbox access after the original session expires or the victim changes their password. CVE-2026-73571 makes these attacks more credible by placing the message in the mailbox as any chosen local user. Rapid7 details five Zimbra flaws enabling password guessing, email impersonation, mailbox access and mail exfiltration

CVE (4)

People (1)

MITRE ATT&CK (5)

Vendors (1)

Products (2)

Tools (1)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.