Low severity · published Aug 17, 2026
CVE-2026-75587
Plaintext pre-auth secret exposure via Desktop App diagnostics report
3.3
CVSS
0.1%
EPSS
No
On KEV
Description
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
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
through 6.2.2 · source: vendor
MD
Mattermost Desktop · Mattermost
before 6.2.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-75587
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-75587
Vendor Advisory
https://mattermost.com/security-updates
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