CVE-2026-26233
Published: Mar 25, 2026
Modified: Mar 27, 2026
CVSS v3.1
4.3
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
| Vendor | Product | Versions |
|---|---|---|
Mattermost | Mattermost | affected 11.4.0 - <= 11.4.0affected 11.3.0 - <= 11.3.1affected 11.2.0 - <= 11.2.3affected 10.11.0 - <= 10.11.11unaffected 11.5.0+4 more versions |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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