Improper Authorization in Zimbra Collaboration - #VU134806
Published: June 18, 2026
Vulnerability identifier: #VU134806
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: N/A
CWE-ID: CWE-285
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Synacor Inc.
Affected software:
Zimbra Collaboration
Zimbra Collaboration
Detailed vulnerability description
The vulnerability allows a remote user to send emails impersonating other users.
The vulnerability exists due to improper access control in delegated send handling when processing delegated send requests. A remote user can send a crafted request to send emails impersonating other users.
Remediation
Install security update from vendor's website.