CVE-2026-115785

Zimbra Collaboration Suite Data Source Test SMTP Command Injection via Unsanitized Email Address

Published Oct 23, 2026 CVSS 3.1 · 4.3 Medium EPSS < 1% KEV · Not listed
Description
An SMTP command injection vulnerability in the data-source testing functionality of Zimbra Collaboration Suite (ZCS) allows an ordinary authenticated user with account options enabled to inject CR/LF into the emailAddress inserted into an SMTP envelope command by a JSON SOAP request. After a successful preliminary POP3 or IMAP login, Zimbra sends the injected commands to the selected SMTP service. If that service accepts the pipelined transaction, the attacker can submit mail with attacker-selected recipients, headers and body content without victim interaction. The vulnerable command-construction path is present in ZCS 10.1.16 and 10.1.20.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Synacor
Synacor zimbra Collaboration Suite
CPEs cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*
Vendors & Products Synacor
Synacor zimbra Collaboration Suite
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Zimbra
Zimbra zimbra Collaboration Suite
Vendors & Products Zimbra
Zimbra zimbra Collaboration Suite
Type Values Removed Values Added
Description An SMTP command injection vulnerability in the data-source testing functionality of Zimbra Collaboration Suite (ZCS) allows an ordinary authenticated user with account options enabled to inject CR/LF into the emailAddress inserted into an SMTP envelope command by a JSON SOAP request. After a successful preliminary POP3 or IMAP login, Zimbra sends the injected commands to the selected SMTP service. If that service accepts the pipelined transaction, the attacker can submit mail with attacker-selected recipients, headers and body content without victim interaction. The vulnerable command-construction path is present in ZCS 10.1.16 and 10.1.20.
Title Zimbra Collaboration Suite Data Source Test SMTP Command Injection via Unsanitized Email Address
Weaknesses CWE-93
References
Metrics cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
rapid7
Published
Updated
Oct 29, 2026, 10:45 AM
Reserved
Oct 23, 2026, 1:40 PM
Status
Analyzed
Published
Oct 23, 2026, 2:17 PM
Modified
Nov 2, 2026, 4:29 PM