CVE-2023-50333 Lack of restriction to manage group names for freshly demoted guests
Freshly demoted guests can modify group names due to stale session permissions, requiring a patch to enforce correct access controls.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2023-50333?
CVE-2023-50333 is a low-severity missing authorization vulnerability in Mattermost Mattermost Server, published on 2 Jan 2024. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Mattermost fails to update the permissions of the current session for a user who was just demoted to guest, allowing freshly demoted guests to change group names.
Weakness: CWE-284
Which versions are affected by CVE-2023-50333?
7 open source packages ship an affected version, including github.com/mattermost/mattermost/server/v8, mattermost and github.com/mattermost/mattermost-server. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/mattermost/mattermost/server/v8 Go | All versions | None |
github.com/mattermost/mattermost/server/v8 Go | All versions | 8.1.7 |
github.com/mattermost/mattermost/server/v8 Go | All versions | 8.1.7 |
mattermost Bitnami | All versions | 8.1.7 |
github.com/mattermost/mattermost-server Go | All versions | None |
github.com/mattermost/mattermost-server/v5 Go | All versions | None |
1 more packages
github.com/mattermost/mattermost-server/v6 Go | All versions | None |
Products include Mattermost Mattermost Server.
How do I fix CVE-2023-50333?
Upgrade github.com/mattermost/mattermost/server/v8 to 8.1.7 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2023-50333 being exploited?
There is no known exploitation of CVE-2023-50333 in the wild and no public exploit code.
Other vulnerabilities in Mattermost Mattermost Server
- CVE-2025-12419 Account takeover on OAuth/OpenID-enabled servers
- CVE-2025-12421 Account Takeover via Code Exchange Endpoint
- CVE-2025-4981 Path Traversal Leading to RCE by Any Authenticated Mattermost User
- CVE-2025-20051 Arbitrary file read via block duplication in Mattermost Boards
- CVE-2025-25279 Arbitrary file read in Mattermost Boards via import & export board archive
Sources
Also known as BIT-mattermost-2023-50333, GHSA-9w97-9rqx-8v4j, GO-2024-2444.