CVE-2026-3109 Missing timestamp validation in Zoom webhook handler

Mattermost Plugins versions =11.4 10.11.11.0 fail to validate webhook request timestamps which allows an attacker to corrupt Zoom meeting state in Mattermost via replayed webhook requests. Mattermost Advisory ID: MMSA-2026-00584...

CVE-2026-3109

Mattermost Plugins in versions

CVE-2026-3109 Missing timestamp validation in Zoom webhook handler

Mattermost Plugins versions =11.4 10.11.11.0 fail to validate webhook request timestamps which allows an attacker to corrupt Zoom meeting state in Mattermost via replayed webhook requests. Mattermost Advisory ID: MMSA-2026-00584...

GO-2026-4812 Mattermost fails to verify run_create permission for empty playbookId in github.com/mattermost/mattermost-plugin-playbooks

Mattermost fails to verify runcreate permission for empty playbookId in github.com/mattermost/mattermost-plugin-playbooks...

Authorization Bypass Through User-Controlled Key

Overview Affected versions of this package are vulnerable to Authorization Bypass Through User-Controlled Key in the comment block modification process. An attacker can alter comments created by other users by leveraging editor permissions without proper authorization checks. Remediation Upgrade...

Authorization Bypass Through User-Controlled Key

Overview Affected versions of this package are vulnerable to Authorization Bypass Through User-Controlled Key in the comment block modification process. An attacker can alter comments created by other users by leveraging editor permissions without proper authorization checks. Remediation Upgrade...

CVE-2026-2462 Admin RCE via Malicious Plugin Upload on CI Test Instances

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...

CVE-2026-2476 MS Teams plugin sensitive config values not properly masked in support packets

Mattermost Plugins versions =2.0.3.0 fail to properly mask sensitive configuration values which allows an attacker with access to support packets to obtain original plugin settings via exported configuration data. Mattermost Advisory ID: MMSA-2026-00606...

CVE-2026-2476 MS Teams plugin sensitive config values not properly masked in support packets

Mattermost Plugins versions =2.0.3.0 fail to properly mask sensitive configuration values which allows an attacker with access to support packets to obtain original plugin settings via exported configuration data. Mattermost Advisory ID: MMSA-2026-00606...

CVE-2026-2476

Mattermost Plugins

Incorrect Authorization

Overview @openclaw/mattermost is an OpenClaw Mattermost channel plugin Affected versions of this package are vulnerable to Incorrect Authorization through improper access control in the pairing store process. An attacker can gain unauthorized access to another account's direct message pairing by...

GO-2026-4525 Mattermost Plugin Zoom fail to validate user identity and post ownership in the {{/api/v1/askPMI}} endpoint in github.com/mattermost/mattermost-plugin-zoom

Mattermost Plugin Zoom fail to validate user identity and post ownership in the /api/v1/askPMI endpoint in github.com/mattermost/mattermost-plugin-zoom...

GO-2026-4519 Mattermost Plugin Zoom allows any logged-in user to change Zoom meeting restrictions for arbitrary channels in github.com/mattermost/mattermost-plugin-zoom

Mattermost Plugin Zoom allows any logged-in user to change Zoom meeting restrictions for arbitrary channels in github.com/mattermost/mattermost-plugin-zoom...

GO-2026-4456 Mattermost Confluence plugin doesn't properly escape user-controlled display names in HTML template rendering in github.com/mattermost/mattermost-plugin-confluence

Mattermost Confluence plugin doesn't properly escape user-controlled display names in HTML template rendering in github.com/mattermost/mattermost-plugin-confluence...

Mattermost Plugin Zoom allows any logged-in user to change Zoom meeting restrictions for arbitrary channels

Mattermost versions 11.1.x = 11.1.2, 10.11.x = 10.11.9, 11.2.x = 11.2.1 and Mattermost Plugin Zoom versions =1.11.0 fail to validate the authenticated user when processing /plugins/zoom/api/v1/channel-preference, which allows any logged-in user to change Zoom meeting restrictions for arbitrary...

Missing Authorization

Overview Affected versions of this package are vulnerable to Missing Authorization via the /api/v1/askPMI endpoint. An attacker can initiate meetings as other users and modify posts without authorization by sending crafted API requests with manipulated user IDs and post data. Remediation Upgrade...

CVE-2025-13523 Cross-Site Scripting (XSS) via Unescaped Display Names in Mattermost Confluence Plugin OAuth2 Flow

Mattermost Confluence plugin version 1.7.0 fails to properly escape user-controlled display names in HTML template rendering which allows authenticated Confluence users with malicious display names to execute arbitrary JavaScript in victim browsers via sending a specially crafted OAuth2 connectio...

PT-2026-6729

Name of the Vulnerable Software and Affected Versions Mattermost Confluence plugin versions prior to 1.7.0 Description The Mattermost Confluence plugin does not properly sanitize user-controlled display names when rendering HTML templates. This allows authenticated Confluence users with malicious...

GO-2026-4275 Mattermost with Jira plugin enabled has Incorrect Implementation of Authentication Algorithm in github.com/mattermost/mattermost-plugin-jira

Mattermost with Jira plugin enabled has Incorrect Implementation of Authentication Algorithm in github.com/mattermost/mattermost-plugin-jira. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions. If this is...

GO-2025-4254 Mattermost has CSRF vulnerability via Calls Widget page in github.com/mattermost/mattermost-plugin-calls

Mattermost has CSRF vulnerability via Calls Widget page in github.com/mattermost/mattermost-plugin-calls...