CVE-2026-10632

High

Description

A reflected cross-site scripting vulnerability in the Classic Web Client of Zimbra Collaboration Suite (ZCS) allows an attacker to inject JavaScript through the packages parameter of the /h/rest document editor. The editor inserts package names into script attributes without HTML encoding. When combined with CVE-2026-50053, an attacker with an ordinary Zimbra account can supply their own authentication token and document identifiers in a URL and execute JavaScript in another signed-in user's Zimbra browser session when that user opens the URL. This permits reading mailbox data and performing authenticated actions as the victim. The issue affects ZCS 10.1.16 and was remediated in 10.1.17.

SeverityHigh
CVSS8.7
Exploit probability—
ProductZimbra Collaboration Suite
PublishedOct 23, 2026
First seenOct 23, 2026

How to fix

Update
  • Zimbra Zimbra Collaboration Suite10.1.17 or later

Affected products

ProductAffected versionsFixed in
Zimbra Zimbra Collaboration Suitev < 10.1.1710.1.17

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