CVE-2018-21251 json
An issue was discovered in Mattermost Server before 5.2 and 5.1.1.
published 2020-06-19 6 y ago modified 2026-06-17 4 mo ago also EUVD-2018-13766
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.2%
- EPSS 1.2% chance of exploitation in 30 days, percentile 68%
- public exploits
- 0
- none known
Summary
An issue was discovered in Mattermost Server before 5.2 and 5.1.1. Authorization could be bypassed if the channel name were not the same in the params and the body.
Patch / fix
- mattermost mattermost_server 5.1.1
Exploit prediction
1.20% chance of exploitation in the next 30 days, higher than 68% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-862 Missing Authorization
References
-
mattermost.com
/security-updates/
vendor-advisory
Sources
- CVE List CVE-2018-21251
- NVD CVE-2018-21251
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.