GO-2026-4746
Mattermost fails to canonicalize IPv4-mapped IPv6 addresses before reserved IP validation in github.com/mattermost/mattermost-server
Quick fix
GO-2026-4746 — github.com/mattermost/mattermost-server: upgrade to the fixed version with the command below.
go get github.com/mattermost/mattermost-server@v10.11.11+incompatibleDetails
Mattermost fails to canonicalize IPv4-mapped IPv6 addresses before reserved IP validation in github.com/mattermost/mattermost-server.
NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions.
(If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.)
The additional affected modules and versions are: github.com/mattermost/mattermost-server/v5 before v5.3.2-0.20260129133647-5d787969c2d5.
Are you affected?
Enter the version of the package you're using.
Affected packages
10.11.0-rc1+incompatibleFixed in: 10.11.11+incompatiblego get github.com/mattermost/mattermost-server@v10.11.11+incompatible0No fixed version published yet for github.com/mattermost/mattermost-server/v5 (go modules). Pin to a known-safe version or switch to an alternative.
0No fixed version published yet for github.com/mattermost/mattermost-server/v6 (go modules). Pin to a known-safe version or switch to an alternative.
0Fixed in: 8.0.0-20260129133647-5d787969c2d5go get github.com/mattermost/mattermost/server/v8@v8.0.0-20260129133647-5d787969c2d5