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TI-2026-52899 Aliases CVE-2026-75587GHSA-jq35-5w25-hqv7

Plaintext pre-auth secret exposure via Desktop App diagnostics report

Priority LOW 16CWE-200Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-200.

Summary

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00133 2nd percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 6.3.0, 6.2.3.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MattermostMattermostup to 6.2.26.3.0, 6.2.3.0Patch availableCNA
  • Mattermost VendorMattermost Affected up to 6.2.2 Fixed in 6.3.0, 6.2.3.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*before 6.2.3VulnerableMattermost
  • cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:* Versions before 6.2.3 Vulnerable ·Mattermost

Remediation

  • Fix · CNA Mattermost (Mattermost) Fixed in 6.3.0, 6.2.3.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-75587
  2. 2026-10-03 Alias added: GHSA-jq35-5w25-hqv7

References

Advisory 1

  • TI-2019-15074 An issue was discovered in Mattermost Desktop App before 4.3.0 on macOS. CVSS 3.1CRITICAL 9.8
  • TI-2016-09099 An issue was discovered in Mattermost Desktop App before 3.4.0. CVSS 3.1CRITICAL 9.8
  • TI-2019-15079 An issue was discovered in Mattermost Desktop App before 4.2.2. CVSS 3.1HIGH 8.8
  • TI-2024-26542 RCE in desktop app in Windows by local attacker CVSS 3.1HIGH 7.8
  • TI-2026-05712 Mattermost Desktop App fails to restrict the allow list of domains which NTLM credentials are passed CVSS 3.1HIGH 7.7
  • TI-2026-00781 Arbitrary application execution via unvalidated server-controlled URLs in Help menu CVSS 3.1HIGH 7.6
See all 33 →

Sources