Mattermost security updates 9.8.1 / 9.7.5 / 9.6.3 / 9.5.6 (ESR) released

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

The security update is available for Mattermost dot releases 9.8.1, 9.7.5, 9.6.3, and 9.5.6 (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 v9.8.1 version also includes the following fixes:

• Removed a safety limit error message in compiled Team Edition and unlicensed Enterprise Edition deployments when message count exceeds 5 million posts.
• Fixed an issue with some plugin settings with defaults not changing value.

The v9.6.3 version also includes the following fix:

• Fixed an issue with some plugin settings with defaults not changing value.

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