CVE-2026-75587: Plaintext pre-auth secret exposure via Desktop App diagnostics report
Mattermost Desktop App versions <=6.2 6.2.2.0 fail to redact the pre-auth secret when generating a diagnostics report, which allows a local attacker with access to a user's diagnostics report or log files to obtain the plaintext pre-auth secret configured for a connected server via inspecting the Server Connectivity (Step-3) diagnostics output. Mattermost Advisory ID: MMSA-2026-00716
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
mattermost-desktop-appto a version that resolves this vulnerability.Fixed in 6.3.0 - Upgrade
Upgrade
mattermost-desktop-appto a version that resolves this vulnerability.Fixed in 6.2.3.0
Event History
Frequently Asked Questions
What is the severity of CVE-2026-75587?
CVE-2026-75587 has a severity rating of low, with a score of 3.6.
How do I fix CVE-2026-75587?
To address CVE-2026-75587, update the Mattermost Desktop App to version 6.2.2.1 or later, which resolves the issue.
What type of vulnerability is CVE-2026-75587?
CVE-2026-75587 is classified as an information disclosure vulnerability due to the exposure of plaintext pre-auth secrets.
Who is affected by CVE-2026-75587?
Users of Mattermost Desktop App versions 6.2 and earlier may be affected by CVE-2026-75587.
Can a remote attacker exploit CVE-2026-75587?
No, CVE-2026-75587 requires local access to the user's diagnostics report or log files to exploit the vulnerability.