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.
Affected products
synacor: zimbra collaboration suite
References2
- wiki.zimbra.com/wiki/Security_Center Vendor Advisory
- wiki.zimbra.com/wiki/Zimbra_Security_Advisories Vendor Advisory
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 18 · as of 12 November 2026
- CWE
- CWE-863
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