CVE-2026-3116 - Vulnerability Details - OpenCVE

Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause service disruption via the webhook endpoint. Mattermost Advisory ID: MMSA-2026-00589

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required High

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

No data.

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References

Link	Providers
https://mattermost.com/security-updates

History

Thu, 26 Mar 2026 18:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Thu, 26 Mar 2026 16:45:00 +0000

Type	Values Removed	Values Added
Description		Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause service disruption via the webhook endpoint. Mattermost Advisory ID: MMSA-2026-00589
Title		Improper Input Validation in Zoom Plugin Webhook Handler
Weaknesses		CWE-400
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 4.9, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-03-26T16:19:32.607Z

Updated: 2026-03-26T17:51:14.971Z

Reserved: 2026-02-24T11:10:17.757Z

Link: CVE-2026-3116

Vulnrichment

Updated: 2026-03-26T17:47:33.539Z

NVD

Status : Received

Published: 2026-03-26T17:16:42.823

Modified: 2026-03-26T17:16:42.823

Link: CVE-2026-3116

Redhat

No data.

OpenCVE Enrichment

No data.

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