CVE-2026-2299 Improper Access Control in Mattermost Google Drive Plugin File Creation Endpoint
Authenticated users can share files to unauthorized private channels and disclose membership due to missing channel validation in the Google Drive plugin.
- 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-2026-2299?
CVE-2026-2299 is a medium-severity missing authorization vulnerability in Mattermost Google Drive Plugin, published on 25 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The Mattermost Google Drive plugin before version 1.1.0 fails to validate channel membership in the file creation endpoint, allowing authenticated users with a connected Google account to share Google Drive files to unauthorized private channels and disclose private channel membership.
Weakness: CWE-862
Which versions are affected by CVE-2026-2299?
It affects 1 product.
Products include Mattermost Google Drive.
How do I fix CVE-2026-2299?
No fix has been published for CVE-2026-2299 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-2026-2299 being exploited?
There is no known exploitation of CVE-2026-2299 in the wild and no public exploit code.
Sources
Also known as GHSA-m2c6-qhf9-2xm8.