CVE-2024-21848 Users maintain access to active call after being removed from a channel
Removed users can continue participating in active calls, allowing unauthorized access to call content.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-21848?
CVE-2024-21848 is a low-severity missing authorization vulnerability in Mattermost Mattermost Server, published on 5 Apr 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Improper Access Control in Mattermost Server versions 8.1.x before 8.1.11 allows an attacker that is in a channel with an active call to keep participating in the call even if they are removed from the channel
Which versions are affected by CVE-2024-21848?
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 | 8.1.11 |
github.com/mattermost/mattermost/server/v8 Go | All versions | 8.1.11 |
mattermost Bitnami | From 8.1.0 | 8.1.11 |
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-2024-21848?
Upgrade github.com/mattermost/mattermost/server/v8 to 8.1.11 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2024-21848 being exploited?
There is no known exploitation of CVE-2024-21848 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-2024-21848, GHSA-xp9j-8p68-9q93, GO-2024-2707.