CVE-2026-6342
Last modified
CVE-2026-6342 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. 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: MMSA-2026-00601. EPSS estimates a 0.15% chance of exploitation in the next 30 days.
Description
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: MMSA-2026-00601
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost Server | >= 10.13.0, <= 10.13.11 |
| Mattermost | Mattermost Server | >= 11.1.0, <= 11.1.5 |
| Mattermost | Mattermost Server | >= 11.3.0, <= 11.3.4 |
References
- https://mattermost.com/security-updatesVendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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