mattermost security release

Mattermost security updates 9.5.2 (ESR) / 9.4.4 / 9.3.3 / 8.1.11 (ESR) released

We’re informing you about a Mattermost security update, which addresses low- to medium-level severity vulnerabilities. We highly recommend that you apply the update.

The security update is available for Mattermost dot releases 9.5.2 (Extended Support Release), 9.4.4, 9.3.3, 8.1.11 (Extended Support Release), for both Team Edition and Enterprise Edition. They are available for download here.

Customer safety and data security are the utmost priorities for Mattermost. For our customers’ protection, and as outlined in our Responsible Disclosure policy, Mattermost does not disclose specifics on this vulnerability until 30 days after this announcement. After 30 days, we will publish specific details on the vulnerability on our Security Updates webpage.

The v8.1.11 version also includes the following change:

  • Pre-packaged Calls version v0.23.1.

The v9.5.2 version also includes the following change:

  • Fixed ChannelHasBeenCreated plugin hook not being called when a group channel is created.

You can follow the standard upgrade instructions to apply the updates.


Amy Blais is the Release Manager at Mattermost, Inc. Her other roles include Community and Customer Support. She previously served as the company’s Associate Marketing Manager.