CVE-2025-8285 Unauthorized Channel Subscription Creation in Mattermost Confluence Plugin

What is CVE-2025-8285?

CVE-2025-8285 is a medium-severity missing authorization vulnerability in Mattermost Confluence Plugin, published on 11 Aug 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Mattermost Confluence Plugin version <1.5.0 fails to check the access of the user to the channel which allows attackers to create channel subscription without proper access to the channel via API call to the create channel subscription endpoint.

Weakness: CWE-862

Which versions are affected by CVE-2025-8285?

3 open source packages ship an affected version, including github.com/mattermost/mattermost-plugin-confluence. It affects 1 product.

Products include Mattermost Confluence.

How do I fix CVE-2025-8285?

Upgrade github.com/mattermost/mattermost-plugin-confluence to 1.5.0 or later.

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

Is CVE-2025-8285 being exploited?

There is no known exploitation of CVE-2025-8285 in the wild and no public exploit code.

Other vulnerabilities in Mattermost Confluence Plugin

• CVE-2025-13523 Cross-Site Scripting (XSS) via Unescaped Display Names in Mattermost Confluence Plugin OAuth2 Flow High 7.7
• CVE-2025-52931 Unexpected input to Update Channel Subscription endpoint causes DoS in Mattermost Confluence Plugin High 7.5
• CVE-2025-54525 Unexpected input to Create Channel Subscription endpoint causes DoS in Mattermost Confluence Plugin High 7.5
• CVE-2025-44004 Unauthenticated Channel Subscription Creation in Mattermost Confluence Plugin High 7.2
• CVE-2025-54478 Unauthenticated Channel Subscription Edit in Mattermost Confluence Plugin High 7.2

Sources

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

Also known as GHSA-qjrx-j8wm-xf83, GO-2025-3868.