CVE-2026-3113

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to set permissions on downloaded bulk export which allows other local users on the server to be able to read contents of the bulk export. Mattermost Advisory ID: MMSA-2026-00593.

A file, directory, or other resource is assigned permissions that allow broader access than intended. Typical impact: unauthorized read, modification, or execution of the resource.

CVE-2026-3113 has a CVSS score of 5.0 (Medium). The vector is requires local access, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (11.4.1, 11.3.2, 11.2.4, 10.11.12, 8.0.0-20260217110922-b7d4a1f1f59b); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2026-3113? CVE-2026-3113 is a medium-severity incorrect permission assignment for critical resource vulnerability in github.com/mattermost/mattermost-server (go), affecting versions >= 11.4.0-rc1, < 11.4.1. It is fixed in 11.4.1, 11.3.2, 11.2.4, 10.11.12, 8.0.0-20260217110922-b7d4a1f1f59b. A file, directory, or other resource is assigned permissions that allow broader access than intended.
2. How severe is CVE-2026-3113? CVE-2026-3113 has a CVSS score of 5.0 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of github.com/mattermost/mattermost-server are affected by CVE-2026-3113? github.com/mattermost/mattermost-server (go) versions >= 11.4.0-rc1, < 11.4.1 is affected.
4. Is there a fix for CVE-2026-3113? Yes. CVE-2026-3113 is fixed in 11.4.1, 11.3.2, 11.2.4, 10.11.12, 8.0.0-20260217110922-b7d4a1f1f59b. Upgrade to this version or later.
5. Is CVE-2026-3113 exploitable, and should I be worried? Whether CVE-2026-3113 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-3113 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-3113?
   • Upgrade github.com/mattermost/mattermost-server to 11.4.1 or later
   • Upgrade github.com/mattermost/mattermost-server to 11.3.2 or later
   • Upgrade github.com/mattermost/mattermost-server to 11.2.4 or later
   • Upgrade github.com/mattermost/mattermost-server to 10.11.12 or later
   • Upgrade github.com/mattermost/mattermost-server to 8.0.0-20260217110922-b7d4a1f1f59b or later