CVE-2026-2454 (GCVE-0-2026-2454)

Vulnerability from cvelistv5 – Published: 2026-03-16 20:10 – Updated: 2026-03-17 13:37
VLAI?
Title
DoS in Calls plugin via malformed msgpack in websocket request.
Summary
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to handle incorrectly reported array lengths which allows malicious user to cause OOM errors and crash the server via sending corrupted msgpack frames within websocket messages to calls plugin. Mattermost Advisory ID: MMSA-2025-00537
Severity ?
5.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
CWE
  • CWE-1287 - Improper Validation of Specified Type of Input
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.3.0 , ≤ 11.3.0 (semver)
Affected: 11.2.0 , ≤ 11.2.2 (semver)
Affected: 10.11.0 , ≤ 10.11.10 (semver)
Unaffected: 11.4.0
Unaffected: 11.3.1
Unaffected: 11.2.3
Unaffected: 10.11.11
Create a notification for this product.
Credits
National Security Agency
Show details on NVD website
To clipboard 

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • 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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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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