Description
An issue was discovered in Mattermost Server before 4.4.3 and 4.3.3. Attackers could reconfigure an OAuth app in some cases where Mattermost is an OAuth 2.0 service provider.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | govulncheck-vulndb | 0.0.20251105T184115-1.1 | openSUSE-SU-2025:15710-1 |
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260723T184607-160000.1.1 | openSUSE-SU-2026:21483-1 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Go | github.com/mattermost/mattermost-server | < 4.3.3 | 4.3.3 | GHSA-hgrp-fgm8-56g8 |
| Go | github.com/mattermost/mattermost-server | >= 4.4.0-rc1, < 4.4.3 | 4.4.3 | GHSA-hgrp-fgm8-56g8 |
| Go | github.com/mattermost/mattermost-server | < 4.3.3+incompatible · >= 4.4.0-rc1+incompatible, < 4.4.3+incompatible | 4.3.3+incompatible, 4.4.3+incompatible | GO-2025-4075 |
Advisories 2
- openSUSE-SU-2026:21483-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Jul 31, 2026
- openSUSE-SU-2025:15710-1 govulncheck-vulndb-0.0.20251105T184115-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026