CVE-2026-26233 (GCVE-0-2026-26233)

Vulnerability from cvelistv5 – Published: 2026-03-25 16:24 – Updated: 2026-03-27 14:59
VLAI?
Title
Denial of Service via HTTP/2 single packet attack on login endpoint
Summary
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
Severity ?
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.4.0 , ≤ 11.4.0 (semver)
Affected: 11.3.0 , ≤ 11.3.1 (semver)
Affected: 11.2.0 , ≤ 11.2.3 (semver)
Affected: 10.11.0 , ≤ 10.11.11 (semver)
Unaffected: 11.5.0
Unaffected: 11.4.1
Unaffected: 11.3.2
Unaffected: 11.2.4
Unaffected: 10.11.12
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Credits
Axel Larsson & Jakob Ristner
Show details on NVD website
To clipboard 

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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