CVE-2018-21258: Mattermost Server is vulnerable to a Denial of Service attack through `invite_people` command

May 24, 2022 (updated November 20, 2025)

An issue was discovered in Mattermost Server before 5.1.0. It allows attackers to cause a denial of service via the invite_people slash command.

References

github.com/advisories/GHSA-5mh6-p63g-3mv5
github.com/mattermost/mattermost
github.com/mattermost/mattermost/commit/af615ffc24b774d76deef8c93282831432669dd8
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2018-21258

Code Behaviors & Features

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