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GO-2026-5838
Mattermost doesn't properly validate msgpack-encoded WebSocket frames before memory allocation in github.com/mattermost/mattermost-server
Details
Mattermost doesn't properly validate msgpack-encoded WebSocket frames before memory allocation in github.com/mattermost/mattermost-server
Are you affected?
Enter the version of the package you're using.
Affected packages
Go / github.com/mattermost/mattermost-server
Introduced in:
10.11.0+incompatible Fixed in: 10.11.15+incompatible Fix
go get github.com/mattermost/mattermost-server@v10.11.15+incompatible Go / github.com/mattermost/mattermost-server/v5
Introduced in:
0 No fixed version published yet for github.com/mattermost/mattermost-server/v5 (go modules). Pin to a known-safe version or switch to an alternative.
Go / github.com/mattermost/mattermost-server/v6
Introduced in:
0 No fixed version published yet for github.com/mattermost/mattermost-server/v6 (go modules). Pin to a known-safe version or switch to an alternative.
Go / github.com/mattermost/mattermost/server/v8
Introduced in:
0 Fixed in: 8.0.0-20260410202636-17939826efa2 Fix
go get github.com/mattermost/mattermost/server/v8@v8.0.0-20260410202636-17939826efa2