CVE-2026-6346

HIGH

Sensitive credentials exposed in plaintext in Mattermost support packets

Title source: cna
STIX 2.1

Description

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields before including them in support packet generation, which allows a Mattermost System Admin or any party with access to a support packet to obtain sensitive credentials in plaintext via downloading a support packet from the System Console.. Mattermost Advisory ID: MMSA-2026-00607

References (1)

Core 1
Core References
Vendor Advisory vendor-advisory
MMSA-2026-00607
https://mattermost.com/security-updates

Scores

CVSS v3 8.7
EPSS 0.0003
EPSS Percentile 8.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-200
Status published
Products (8)
Mattermost/Mattermost 10.11.0 - 10.11.13
Mattermost/Mattermost 10.11.14
Mattermost/Mattermost 11.4.0 - 11.4.3
Mattermost/Mattermost 11.4.4
Mattermost/Mattermost 11.5.0 - 11.5.1
Mattermost/Mattermost 11.5.2
Mattermost/Mattermost 11.6.0
mattermost/mattermost_server 10.11.0 - 10.11.14
Published May 18, 2026
Tracked Since May 18, 2026