Vulnerability Database

299,759

Total vulnerabilities in the database

CVE-2018-21256

An issue was discovered in Mattermost Server before 5.1. It allows attackers to bypass intended access restrictions (for group-message channel creation) via the Group message slash command.

  • Published: Jun 19, 2020
  • Updated: Nov 9, 2025
  • CVE: CVE-2018-21256
  • Severity: Low
  • Exploit:

CVSS v3:

  • Severity: Low
  • Score: 4.3
  • AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

CVSS v2:

  • Severity: Low
  • Score: 4
  • AV:N/AC:L/Au:S/C:N/I:P/A:N

CWEs:

Software From Fixed in
mattermost / mattermost_server - 5.1.0