CVE-2023-5193 System Role with manage posts permission can read posts of Direct Messages

What is CVE-2023-5193?

CVE-2023-5193 is a medium-severity missing authorization vulnerability in Mattermost Mattermost, published on 29 Sep 2023. An attacker needs administrator access to exploit it, with no action from the victim.

Official description

Mattermost fails to properly check permissions when retrieving a post allowing for a System Role with the permission to manage channels to read the posts of a DM conversation.

Weakness: CWE-863

Which versions are affected by CVE-2023-5193?

6 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-2023-5193?

Upgrade github.com/mattermost/mattermost/server/v8 to a fixed version for your release line: 8.0.2 or 8.1.1.

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

Is CVE-2023-5193 being exploited?

There is no known exploitation of CVE-2023-5193 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-h8wh-f7gw-fwpr.