CVE-2018-21254 json
An issue was discovered in Mattermost Server before 5.1.
published 2020-06-19 6 y ago modified 2026-06-17 4 mo ago also EUVD-2018-13769
- cvss
- 4.3
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 49%
- public exploits
- 0
- none known
Summary
An issue was discovered in Mattermost Server before 5.1. An attacker can bypass intended access control (for direct-message channel creation) via the Message slash command.
Patch / fix
- mattermost mattermost_server 5.1.0
Exploit prediction
0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N |
| NVD | 2.0 | 4.0 | AV:N/AC:L/Au:S/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-732 Incorrect Permission Assignment for Critical Resource
References
-
mattermost.com
/security-updates/
vendor-advisory
Sources
- CVE List CVE-2018-21254
- NVD CVE-2018-21254
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