| Package | Affected versions | Patched versions |
|---|---|---|
| github.com/mattermost/mattermost-server | ≥ 10.11.0, < 10.11.15≥ 10.11.0+incompatible, < 10.11.15+incompatible≥ 11.4.0, < 11.4.5≥ 11.4.0+incompatible, < 11.4.5+incompatible≥ 11.5.0, < 11.5.4≥ 11.5.0+incompatible, < 11.5.4+incompatible≥ 11.6.0, < 11.6.1≥ 11.6.0+incompatible, < 11.6.1+incompatible | 10.11.1510.11.15+incompatible11.4.511.4.5+incompatible11.5.411.5.4+incompatible11.6.111.6.1+incompatible |
| github.com/mattermost/mattermost-server/v5 | all versions | |
| github.com/mattermost/mattermost-server/v6 | all versions | |
| github.com/mattermost/mattermost/server/v8 | < 8.0.0-20260407102538-faa7d75b4ea0 | 8.0.0-20260407102538-faa7d75b4ea0 |
| mattermost server | ≥ 10.11.0, < 10.11.15 |
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to filter nil elements from outgoing webhook attachment payloads before processing, which allows an authenticated user to cause a denial of service (server process termination) via a crafted webhook callback response containing a null attachment entry. Mattermost Advisory ID: MMSA-2026-00641
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Scan my site free≥ 11.4.0, < 11.4.5≥ 11.5.0, < 11.5.4≥ 11.6.0, < 11.6.110.11.1511.4.511.5.411.6.1 |