CVE-2025-12559 - CVE House
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Status published Medium CVE-2025-12559

Information Disclosure in Common Teams API

Vulnerability Description

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

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • hainguyen0207

References

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Affected Vendor

Affected Software

Mattermost
Vulnerable Versions:
11.0.0, 10.12.0, 10.11.0, 10.5.0, 11.1.0, 11.0.3, 10.12.2, 10.11.5, 10.5.13

Timeline

Official Publish: November 27th, 2025
Last Modified: November 28th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Weaknesses (CWE)

CWE-200

MITRE ATT&CK TTPs

T1213 Data from Information Repositories
Collection
T1005 Data from Local System
Collection
T1552 Unsecured Credentials
Credential Access
T1041 Exfiltration Over C2 Channel
Exfiltration