8 matches found
PT-2026-60737
Name of the Vulnerable Software and Affected Versions Mattermost Desktop App versions 5.5.13 Mattermost Desktop App versions 6.0.2.0 Mattermost Desktop App versions prior to 6.3 Description The application fails to properly perform a null check when verifying headers. This allows a user to cause...
CVE-2026-9824 Remote cluster metadata enumeration via /share-channel autocomplete
Mattermost versions 11.7.x = 11.7.2, 11.6.x = 11.6.4, 10.11.x = 10.11.19 fail to check the managesharedchannels permission in the /share-channel autocomplete handler, which allows an authenticated user without that permission to enumerate configured remote cluster connection metadata via slash...
CVE-2026-6739 Mattermost: Delegated admins could patch protected default system roles
Mattermost versions 11.6.x = 11.6.1, 11.5.x = 11.5.4, 10.11.x = 10.11.15, 10.11.x = 10.11.16 fail to require system-level permission when patching protected default system roles, which allows authenticated users with delegated user-management permissions to escalate privileges by altering built-i...
CVE-2026-3471 Opening a window with {{javascript:alert()}} as URL causes crash in the Mattermost Desktop App
Mattermost Desktop App versions =6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App which allows a malicious server owner to repeated crash the application via calling window.open'javascript:alert';. Mattermost Advisory ID: MMSA-2026-00...
CVE-2026-4286
Mattermost versions 11.5.x = 11.5.1, 10.11.x = 10.11.13 fail to check if teamid was being changed when updating playbooks, allowing users with only Manage Playbook Configurations permission to change a playbook's team, bypassing manage members restriction via PUT api. Mattermost Advisory ID:...
CVE-2026-1629
Mattermost CVE-2026-1629 affects Mattermost 10.11.x up to 10.11.10. The issue arises from not invalidating cached permalink preview data when a user loses channel access, allowing continued viewing of private channel content via previously cached previews until cache reset or relogin. The CVSSv3....
CVE-2026-4265 Guest user can upload files without permission across teams
Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to validate team-specific uploadfile permissions which allows a guest user to post files in channels where they lack uploadfile permission via uploading files in a team where they have permission and reusing the file...