CVE-2025-27715
LOWCVSS Vector
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:N
Lifecycle Timeline
3Description
Mattermost versions 9.11.x <= 9.11.8 fail to prompt for explicit approval before adding a team admin to a private channel, which team admins to joining private channels via crafted permalink links without explicit consent from them.
Analysis
Mattermost versions 9.11.x <= 9.11.8 fail to prompt for explicit approval before adding a team admin to a private channel, which team admins to joining private channels via crafted permalink links. Rated low severity (CVSS 3.3), this vulnerability is remotely exploitable. No vendor patch available.
Technical Context
This vulnerability is classified as Incorrect Authorization (CWE-863), which allows attackers to bypass authorization checks to access restricted resources. Mattermost versions 9.11.x <= 9.11.8 fail to prompt for explicit approval before adding a team admin to a private channel, which team admins to joining private channels via crafted permalink links without explicit consent from them. Affected products include: Mattermost Mattermost Server.
Affected Products
Mattermost Mattermost Server.
Remediation
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Review and test authorization logic, implement consistent access control checks, use centralized authorization framework.
Priority Score
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External POC / Exploit Code
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