high7.5
CVE-2026-24458
Mattermost fails to properly handle very long passwords
Impact
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly handle very long passwords, which allows an attacker to overload the server CPU and memory via executing login attempts with multi-megabyte passwords. Mattermost Advisory ID: MMSA-2026-00587
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/mattermost/mattermost/server/v8 | < 8.0.0-20260129164748-7201f42d955f | 8.0.0-20260129164748-7201f42d955f |
| go | github.com/mattermost/mattermost-server | < 5.3.2-0.20260129164748-7201f42d955f | 5.3.2-0.20260129164748-7201f42d955f |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Mattermost | Mattermost Server | from 10.11.0 before 10.11.11 from 11.2.0 before 11.2.3 from 11.3.0 before 11.3.1 |