mattermost security release

Mattermost security updates Desktop app v5.5.1 and Mobile app v2.8.1 released

We’re informing you about a Mattermost security update, which addresses the vulnerability CVE-2023-4863 of the third-party library libwebp which was affecting the Desktop app and the Mobile iOS app. We highly recommend that you apply the update.

The security update is available for Mattermost dot releases Desktop app v5.5.1 and Mobile app v2.8.1. 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.


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.