CVE-2026-6346: Mattermost doesn't sanitize sensitive configuration fields before including them in support packet generation

May 18, 2026 (updated June 1, 2026)

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

github.com/advisories/GHSA-9p64-jpc7-m2rp
github.com/mattermost/mattermost/commit/fac92f4a71f356009e27983a980f729f599e8ba5
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2026-6346

Code Behaviors & Features

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