CVE-2023-49809 Todo plugin gets crashed and disabled by member
A member can crash and disable the Todo plugin by sending null request bodies to the add endpoint, causing a denial of service.
- 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-2023-49809?
CVE-2023-49809 is a medium-severity denial of service vulnerability in Mattermost Mattermost Server, published on 12 Dec 2023. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Mattermost fails to handle a null request body in the /add endpoint, allowing a simple member to send a request with null request body to that endpoint and make it crash. After a few repetitions, the plugin is disabled.
Weakness: CWE-400
Which versions are affected by CVE-2023-49809?
1 open source package ship an affected version, including mattermost. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mattermost Bitnami | All versions | 8.1.6, 9.1.1 |
Products include Mattermost Mattermost Server.
How do I fix CVE-2023-49809?
Upgrade mattermost to a fixed version for your release line: 8.1.6 or 9.1.1.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-49809 being exploited?
There is no known exploitation of CVE-2023-49809 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-2023-49809, GHSA-478w-7mxw-36gh.