CVE-2023-6202 Insecure Direct Object Reference in /plugins/focalboard/ api/v2/users of Mattermost Boards

What is CVE-2023-6202?

CVE-2023-6202 is a medium-severity missing authorization vulnerability in Mattermost Mattermost, published on 27 Nov 2023. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

Mattermost fails to perform proper authorization in the /plugins/focalboard/api/v2/users endpoint allowing an attacker who is a guest user and knows the ID of another user to get their information (e.g. name, surname, nickname) via Mattermost Boards.

Weakness: CWE-284

Which versions are affected by CVE-2023-6202?

8 open source packages ship an affected version, including github.com/mattermost/mattermost/server/v8 and github.com/mattermost/mattermost-server/v6. It affects 1 product.

Products include Mattermost Mattermost.

How do I fix CVE-2023-6202?

Upgrade github.com/mattermost/mattermost/server/v8 to a fixed version for your release line: 8.1.4, 9.0.2 or 9.1.1.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2023-6202 being exploited?

There is no known exploitation of CVE-2023-6202 in the wild and no public exploit code.

Other vulnerabilities in Mattermost Mattermost

• CVE-2019-20851 Path traversal in n/a Critical 9.1
• CVE-2024-39274 Malicious remote can add users to arbitrary teams and channels High 8.7
• CVE-2024-39777 Malicious remote can invite itself to an arbitrary local channel High 8.7
• CVE-2024-39830 Timing attack during remote cluster token comparison when shared channels are enabled High 8.1
• CVE-2023-3615 Lack of server certificate validation in websockets connection High 8.1

All Mattermost Mattermost vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-85jj-c9jr-9jhx.