Vulnerabilidades

Mattermost fails to properly validate a RegExp built off the server URL path, allowing an attacker in control of an enrolled server to mount a Denial Of Service.

Mattermost Desktop fails to correctly handle permissions or prompt the user for consent on certain sensitive ones allowing media exploitation from a malicious mattermost server

Mattermost Mobile fails to limit the maximum number of Markdown elements in a post allowing an attacker to send a post with hundreds of emojis to a channel and freeze the mobile app of users when viewing that particular channel.

Mattermost Desktop fails to set an appropriate log level during initial run after fresh installation resulting in logging all keystrokes including password entry being logged.

Mattermost fails to deduplicate input IDs allowing a simple user to cause the application to consume excessive resources and possibly crash by sending a specially crafted request to /api/v4/users/ids with multiple identical IDs.

Mattermost fails to properly check the creator of an attached file when adding the file to a draft post, potentially exposing unauthorized file information.

Mattermost fails to enforce a limit for the size of the cache entry for OpenGraph data allowing an attacker to send a specially crafted request to the /api/v4/opengraph filling the cache and turning the server unavailable.

Mattermost fails to check the Show Full Name option at the /api/v4/teams/TEAM_ID/top/team_members endpoint allowing a member to get the full name of another user even if the Show Full Name option was disabled

Mattermost fails to enforce character limits in all possible notification props allowing an attacker to send a really long value for a notification_prop resulting in the server consuming an abnormal quantity of computing resources and possibly becoming temporarily unavailable for its users.

Mattermost fails to properly validate the permissions when soft deleting a team allowing a team member to soft delete other teams that they are not part of

Mattermost fails to properly validate permissions when demoting and deactivating a user allowing for a system/user manager to demote / deactivate another manager

Mattermost fails to properly check permissions when retrieving a post allowing for a System Role with the permission to manage channels to read the posts of a DM conversation.

Mattermost fails to properly verify the permissions when managing/updating a bot allowing a User Manager role with user edit permissions to manage/update bots.

Mattermost fails to restrict which parameters' values it takes from the request during signup allowing an attacker to register users as inactive, thus blocking them from later accessing Mattermost without the system admin activating their accounts.

Mattermost fails to sanitize post metadata during audit logging resulting in permalinks contents being logged

Mattermost fails to properly validate the requesting user permissions when updating a system admin, allowing a user manager to update a system admin's details such as email, first name and last name.

Mattermost fails to check if the requesting user is a guest before performing different actions to public playbooks, resulting a guest being able to view, join, edit, export and archive public playbooks.

Mattermost fails to delete the attachments when deleting a message in a thread allowing a simple user to still be able to access and download the attachment of a deleted message

Mattermost iOS app fails to properly validate the server certificate while initializing the TLS connection allowing a network attacker to intercept the WebSockets connection.

Mattermost fails to properly validate a gif image file, allowing an attacker to consume a significant amount of server resources, making the server unresponsive for an extended period of time by linking to specially crafted image file.

Mattermost WelcomeBot plugin fails to to validate the membership status when inviting or adding users to channels allowing guest accounts to be added or invited to channels by default.

Mattermost fails to properly validate markdown, allowing an attacker to crash the server via a specially crafted markdown input.

Mattermost fails to invalidate previously generated password reset tokens when a new reset token was created.

Mattermost fails to delete card attachments in Boards, allowing an attacker to access deleted attachments.

Mattermost fails to properly show information in the UI, allowing a system admin to modify a board state allowing any user with a valid sharing link to join the board with editor access, without the UI showing the updated permissions.