Description

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to rate limit login requests which allows unauthenticated remote attackers to cause denial of service (server crash and restart) via HTTP/2 single packet attack with 100+ parallel login requests.. Mattermost Advisory ID: MMSA-2025-00566

INFO

Published Date :

2026-03-25T16:24:47.694Z

Last Modified :

2026-03-25T16:24:47.694Z

Source :

Mattermost
AFFECTED PRODUCTS

The following products are affected by CVE-2026-26233 vulnerability.

Vendors Products
Mattermost
  • Mattermost
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-26233.

URL Resource
https://mattermost.com/security-updates cve-icon cve-icon
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CVSS Vulnerability Scoring System

Detailed values of each vector for above chart.
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Scope
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Integrity Impact
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