CVE-2026-6342

Mattermost plugins vulnerable to a namespace prefix-matching bypass. Affected: Mattermost Plugins versions

CVE-2026-6342

Mattermost Plugins versions =11.5 11.1.5 10.13.11 11.3.4.0 fail to appropriately check for valid namespaces which allows plugin users to create subscriptions to groups that were not whitelisted via creating groups that share the same prefix as a whitelisted group. Mattermost Advisory ID:...

Mattermost Plugins 安全漏洞

Mattermost Plugins is a plugin provided by the American company Mattermost, offering powerful feature extensions and tight integration with servers and network/desktop applications. Versions 11.5, 11.1.5, 10.13.11, and 11.3.4.0 of Mattermost Plugins contain security vulnerabilities. These...

CVE-2026-3117: Missing Authorization

Mattermost Plugins versions =11.5 11.1.5 10.13.11 11.3.4.0 fail to properly check for permissions when processing commands in the Gitlab plugin which allows normal users to uninstall instances or setup webhook connections via the gitlab instance option or the /gitlab webhook option commands...

CVE-2026-6341: Incorrect Authorization

Mattermost Plugins versions =11.5 11.1.5 10.13.11 11.3.4.0 fail to have API-level checks on which groups the user can create issues or attach comments to which allows a user that is member of multiple groups to create issues to a locked group via direct API requests. Mattermost Advisory ID:...

Mattermost Plugins 安全漏洞

Mattermost Plugins is a plugin provided by the American company Mattermost, offering powerful feature extensions and tight integration with servers and network/desktop applications. Versions 11.5, 11.1.5, 10.13.11, and 11.3.4.0 of Mattermost Plugins contain security vulnerabilities. These...

Mattermost Plugins 安全漏洞

Mattermost Plugins is a plugin provided by the American company Mattermost, offering powerful feature extensions and tight integration with servers and network/desktop applications. Versions 11.5, 11.1.5, 10.13.11, and 11.3.4.0 of Mattermost Plugins have security vulnerabilities. These...

CVE-2026-6342: Incorrect Authorization

Mattermost Plugins versions =11.5 11.1.5 10.13.11 11.3.4.0 fail to appropriately check for valid namespaces which allows plugin users to create subscriptions to groups that were not whitelisted via creating groups that share the same prefix as a whitelisted group. Mattermost Advisory ID:...

EUVD-2026-20880

Mattermost Plugins versions =2.3.1 fail to limit the request body size on the /lifecycle webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610...

EUVD-2026-20882

Mattermost Plugins versions =2.1.3.0 fail to limit the request body size on the /changes webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611...

CVE-2026-21388

Mattermost Plugins versions =2.3.1 fail to limit the request body size on the /lifecycle webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610...

CVE-2026-24661 Unbounded Request Body Read in MS Teams Plugin {{/changes}} Webhook Endpoint

Mattermost Plugins versions =2.1.3.0 fail to limit the request body size on the /changes webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611...

CVE-2026-24661 Unbounded Request Body Read in MS Teams Plugin {{/changes}} Webhook Endpoint

Mattermost Plugins versions =2.1.3.0 fail to limit the request body size on the /changes webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611...

CVE-2026-24661

Mattermost Plugins versions =2.1.3.0 fail to limit the request body size on the /changes webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611...

CVE-2026-21388 Unbounded Request Body Read in MS Teams Plugin {{/lifecycle}} Webhook Endpoint

Mattermost Plugins versions =2.3.1 fail to limit the request body size on the /lifecycle webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610...

CVE-2026-21388

CVE-2026-21388 affects Mattermost Plugins versions

CVE-2026-21388

Mattermost Plugins versions =2.3.1 fail to limit the request body size on the /lifecycle webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610...

CVE-2026-21388: Allocation of Resources Without Limits or Throttling

Mattermost Plugins versions =2.3.1 fail to limit the request body size on the /lifecycle webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610...

Mattermost Plugins 安全漏洞

Mattermost Plugins is a plugin provided by the American company Mattermost, offering powerful feature extensions and tight integration with servers and network/desktop applications. Versions of Mattermost Plugins 2.3.1 and earlier contained security vulnerabilities. These vulnerabilities stemmed...

CVE-2026-24661: Allocation of Resources Without Limits or Throttling

Mattermost Plugins versions =2.1.3.0 fail to limit the request body size on the /changes webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611...