CVSS 3.1
8.1 highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:NCVE-2017-18894
An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5, when used as an OAuth 2.0 service provider. Sometimes. resource-owner authorization is bypassed, allowing account takeover.
Severity
- EPSS
- 0.8% chance of exploitation in the next 30 days; higher than 57% of CVEs (scores of 2026-10-31)
- CWE
- CWE-732
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mattermost:mattermost_server
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-gg42-mwr6-p82c | Go | github.com/mattermost/mattermost-server | <4.0.5 | 4.0.5 |
| GHSA-gg42-mwr6-p82c | Go | github.com/mattermost/mattermost-server | >=4.1.0 <4.1.1 | 4.1.1 |
| GHSA-gg42-mwr6-p82c | Go | github.com/mattermost/mattermost-server | >=4.2.0-rc1 <4.2.0 | 4.2.0 |
| GO-2026-4297 | Go | github.com/mattermost/mattermost-server | <4.0.5+incompatible >=4.1.0+incompatible <4.1.1+incompatible >=4.2.0-rc1+incompatible <4.2.0+incompatible | 4.0.5+incompatible, 4.1.1+incompatible, 4.2.0+incompatible |