CVE-2026-6334
Fixed in a distro release EPSS <1%CVSS 3.1
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to enforce client identity binding during the OAuth authorization code redemption flow which allows an authenticated OAuth client to redeem authorization codes issued to a different client via a crafted token exchange request.. Mattermost Advisory ID: MMSA-2026-00570
Products: Mattermost
Fixed upstream
| Ecosystem | Package | Fixed in |
|---|---|---|
| Go | github.com/mattermost/mattermost-server | 5.3.2-0.20260318173148-e9ae890a013b |
| Go | github.com/mattermost/mattermost-server | 10.11.14+incompatible |
| Go | github.com/mattermost/mattermost-server | 11.5.2+incompatible |
| Go | github.com/mattermost/mattermost-server/v5 | no fix |
| Go | github.com/mattermost/mattermost-server/v6 | no fix |
| Go | github.com/mattermost/mattermost/server/v8 | 11.5.2 |
| Go | github.com/mattermost/mattermost/server/v8 | 10.11.14 |
| Go | github.com/mattermost/mattermost/server/v8 | 8.0.0-20260318173148-e9ae890a013b |
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260723T184607-160000.1.1 |