CVE-2026-2325: Mattermost doesn't limit the size of the request body on the start meeting API endpoint

May 18, 2026 (updated June 1, 2026)

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to limit the size of the request body on the start meeting API endpoint, which allows an authenticated attacker to cause resource exhaustion or denial of service via a crafted oversized HTTP POST request to {{/api/v1/meetings}}.. Mattermost Advisory ID: MMSA-2026-00608

References

github.com/advisories/GHSA-m3p3-8frq-q7qh
github.com/mattermost/mattermost-plugin-msteams-meetings/commit/c5892dd169de865504afa2dd02eaeb6287489f7f
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2026-2325

Code Behaviors & Features

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