CVE-2026-93642 Zimbra Collaboration Suite Modern Web Client Stored Cross-Site Scripting via Forged Share Invitation
An attacker can execute stored XSS via forged share invitations, allowing access to victim mailbox data and account takeover.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-93642?
CVE-2026-93642 is a critical cross-site scripting vulnerability in Zimbra Collaboration Suite (ZCS), published on 25 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Modern recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.
Weakness: CWE-79
Which versions are affected by CVE-2026-93642?
How do I fix CVE-2026-93642?
No fix has been published for CVE-2026-93642 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-93642 being exploited?
There is no known exploitation of CVE-2026-93642 in the wild and no public exploit code.
Sources
Also known as GHSA-q762-85g6-px57.