What is CVE-2026-10632?

CVE-2026-10632 is a high-severity vulnerability in Zimbra Collaboration Suite, classified under Cross-site Scripting. CVSS score: 8.7/10. Published 2026-10-23.

How severe is CVE-2026-10632?

High severity. CVSS v3 base score is 8.7 out of 10.

XSS in Zimbra Collaboration Suite

CVE-2026-10632

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.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-10-23 · last modified 2026-10-23.

CVSS v3 metric

CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Zimbra Collaboration Suite

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

wiki.zimbra.com/wiki/Zimbra_Security_Advisories (vendor-advisory)
www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/ (related)

Frequently asked questions

What is CVE-2026-10632?: CVE-2026-10632 is a high-severity vulnerability in Zimbra Collaboration Suite, classified under Cross-site Scripting. CVSS score: 8.7/10. Published 2026-10-23.
How severe is CVE-2026-10632?: High severity. CVSS v3 base score is 8.7 out of 10.