CVE-2026-24661 - Vulnerability Details - OpenCVE

Mattermost Plugins versions <=2.1.3.0 fail to limit the request body size on the {{/changes}} webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact Low

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

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Mattermost

Mattermost

unaffected

Version	Status	Constraints
`0`	affected	≤ 2.1.3
`2.3.2.0`	unaffected	—

No data.

No data.

No data.

Project Subscriptions

No data.

Advisories

No advisories yet.

Fixes

Solution

Update Mattermost Plugins to versions 2.3.2.0 or higher.

Workaround

No workaround given by the vendor.

References

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

History

Thu, 09 Apr 2026 12:15:00 +0000

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

Thu, 09 Apr 2026 10:30:00 +0000

Type	Values Removed	Values Added
Description		Mattermost Plugins versions <=2.1.3.0 fail to limit the request body size on the {{/changes}} webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611
Title		Unbounded Request Body Read in MS Teams Plugin {{/changes}} Webhook Endpoint
Weaknesses		CWE-770
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-04-09T10:12:45.340Z

Updated: 2026-04-09T11:44:35.023Z

Reserved: 2026-02-11T20:56:06.566Z

Link: CVE-2026-24661

Vulnrichment

Updated: 2026-04-09T11:44:30.263Z

NVD

Status : Received

Published: 2026-04-09T11:16:21.047

Modified: 2026-04-09T11:16:21.047

Link: CVE-2026-24661

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-770

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