CVE-2026-2462mediumCWE-863

CVE-2026-2462: medium-severity vulnerability in Mattermost

Admin RCE via Malicious Plugin Upload on CI Test Instances

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.6epss 0.3%
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to restrict plugin installation on CI test instances with default admin credentials which allows an unauthenticated attacker to achieve remote code execution and exfiltrate sensitive configuration data including AWS and SMTP credentials via uploading a malicious plugin after changing the import directory. Mattermost Advisory ID: MMSA-2025-00528
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L
Affected products
Mattermost · Mattermost
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