CVE-2026-9602 | Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to… | CVSS 5.7 MEDIUM

Description

Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to validate payloads sent from the Mattermost Web App to the Desktop App which allows a malicious server owner to crash the Mattermost Desktop App via changing the payload of a method to a malformed one. Mattermost Advisory ID: MMSA-2026-00678

Metadata

CVE ID: CVE-2026-9602
State: PUBLISHED
Assigner: Mattermost
Reserved: 2026-05-26 15:42 UTC
Published: 2026-07-17 10:03 UTC
Last updated: 2026-07-17 12:54 UTC
Primary CWE: CWE-400
CWE-400 Uncontrolled Resource Consumption
Vendor / Product: Mattermost / Mattermost
Sources: cve.org · NVD

Severity & Metrics

5.7 MEDIUM CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
Mattermost	Mattermost	—	0 ≤ 6.0.2, 0 ≤ 5.6.13, 6.3.0, 6.2.1.0 …

Weakness (CWE)

CWE	Source	Description
CWE-400	cna	CWE-400 Uncontrolled Resource Consumption

CVSS scores (1)

Score	Severity	Version	Source	Vector
5.7	MEDIUM	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References (1)

MMSA-2026-00678 https://mattermost.com/security-updates