CVE-2026-10631 Zimbra Collaboration Suite EWS Extension Authorization Bypass via Crafted Composite Folder/Item Identifier
Authenticated users can read arbitrary mailbox items and attachments from other accounts via the EWS FindItem handler.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-10631?
CVE-2026-10631 is a medium-severity missing authorization vulnerability in Zimbra Collaboration Suite, published on 8 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
An authorization bypass in the EWS FindItem handler of Zimbra Collaboration Suite 10.1.0 through 10.1.19 allows an authenticated user with EWS enabled to read complete mailbox items, including raw MIME and attachments, from arbitrary local accounts without a share or delegation grant.
Weakness: CWE-639
Which versions are affected by CVE-2026-10631?
How do I fix CVE-2026-10631?
No fix has been published for CVE-2026-10631 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-10631 being exploited?
There is no known exploitation of CVE-2026-10631 in the wild and no public exploit code.
Sources
Also known as GHSA-7jfc-2g3q-h5mf.