CVE-2025-12559

low-risk
Published 2025-11-27

Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/{channel_id}/common_teams endpoint

Do I need to act?

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0.05% chance of exploitation
EPSS score — low exploit probability
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
4
CVSS 4.3/10 Medium
NETWORK / LOW complexity

Affected Products (1)

Affected Vendors

Mattermost

References (1)

Vendor Advisory https://mattermost.com/security-updates
23
/ 100
low-risk
Severity 18/34 · Moderate
Exploitability 0/34 · Minimal
Exposure 5/34 · Minimal