CVE-2026-21388

low

Description

Mattermost Plugins versions <=2.3.1 fail to limit the request body size on the {{/lifecycle}} webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610

References

https://mattermost.com/security-updates

Details

Source: Mitre, NVD

Published: 2026-04-09

Updated: 2026-04-09

Risk Information

CVSS v2

Base Score: 2.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:N/A:P

Severity: Low

CVSS v3

Base Score: 3.7

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

Severity: Low

EPSS

EPSS: 0.00039