CVE-2026-6346
published 2026-05-18CVE-2026-6346: 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…
PriorityP350high8.7CVSS 3.1
AVNACLPRHUINSCCHIHAN
EPSS
0.29%
21.0th percentile
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
Affected
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github.com | mattermost_mattermost-server | >= 0 < 5.3.2-0.20260326202606-fac92f4a71f3 | 5.3.2-0.20260326202606-fac92f4a71f3 |
| github.com | mattermost_mattermost_server_v8 | >= 0 < 8.0.0-20260326202606-fac92f4a71f3 | 8.0.0-20260326202606-fac92f4a71f3 |
| github.com | mattermost_mattermost_server_v8 | >= 10.11.0 < 10.11.14 | 10.11.14 |
| github.com | mattermost_mattermost_server_v8 | >= 11.4.0 < 11.4.4 | 11.4.4 |
| github.com | mattermost_mattermost_server_v8 | >= 11.5.0 < 11.5.2 | 11.5.2 |
| mattermost | mattermost | 10.11.0 – 10.11.13 | — |
| mattermost | mattermost | 11.4.0 – 11.4.3 | — |
| mattermost | mattermost | 11.5.0 – 11.5.1 | — |
| mattermost | mattermost_server | >= 10.11.0 < 10.11.14 | 10.11.14 |
| mattermost | mattermost_server | >= 11.4.0 < 11.4.4 | 11.4.4 |
| mattermost | mattermost_server | >= 11.5.0 < 11.5.2 | 11.5.2 |
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GHSA
Mattermost doesn't sanitize sensitive configuration fields before including them in support packet generation
ghsa·2026-05-18
CVE-2026-6346 [HIGH] CWE-200 Mattermost doesn't sanitize sensitive configuration fields before including them in support packet generation
Mattermost doesn't sanitize sensitive configuration fields before including them in support packet generation
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
VulDB
Mattermost up to 10.11.13/11.4.3/11.5.1 Configuration information disclosure (EUVD-2026-30754)
vuldb·2026-05-18·CVSS 8.7
CVE-2026-6346 [HIGH] Mattermost up to 10.11.13/11.4.3/11.5.1 Configuration information disclosure (EUVD-2026-30754)
A vulnerability marked as problematic has been reported in Mattermost up to 10.11.13/11.4.3/11.5.1. The impacted element is an unknown function of the component Configuration Handler. This manipulation causes information disclosure.
The identification of this vulnerability is CVE-2026-6346. It is possible to initiate the attack remotely. There is no exploit available.
It is suggested to upgrade the affected component.
GHSA
GHSA-9p64-jpc7-m2rp: Mattermost versions 11
ghsa_unreviewed·2026-05-18
CVE-2026-6346 [HIGH] CWE-200 GHSA-9p64-jpc7-m2rp: Mattermost versions 11
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
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-05-18
Published