CVE-2026-50055

Medium

Description

A policy-enforcement flaw in Zimbra Collaboration Suite allows an authenticated user to bypass disabled mail forwarding by using a Sieve notify action to send copies of email content and headers to an arbitrary address.

SeverityMedium

CVSS6.5

Exploit probability—

Product

Zimbra Collaboration Suite

PublishedOct 8, 2026

First seenOct 8, 2026

Weakness typeCWE-863Incorrect authorization

How to fix

Update

Zimbra Zimbra Collaboration Suite10.1.20 or later

Vendor advisories

wiki.zimbra.com/wiki/Zimbra_Security_Advisories

Affected products

Product	Affected versions	Fixed in
Zimbra Zimbra Collaboration Suite	v < 10.1.20	10.1.20

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