Mattermost versions 9.11.x <= 9.11.6 fail to filter out DMs from the deleted channels endpoint which allows an attacker to infer user IDs and other metadata from deleted DMs if someone had manually marked DMs as deleted in the database.

An issue was discovered in Mattermost Server before 4.1.0, 4.0.4, and 3.10.3. It allows attackers to discover team invite IDs via team API endpoints.

An issue was discovered in Mattermost Server before 4.1.0, 4.0.4, and 3.10.3. It allows attackers to discover a team invite ID by requesting a JSON document.

An issue was discovered in Mattermost Server before 3.8.2, 3.7.5, and 3.6.7. Weak hashing was used for e-mail invitations, OAuth, and e-mail verification tokens.

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. It allows attackers to obtain sensitive information (user statuses) via a REST API version 4 endpoint.

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It discloses the team creator's e-mail address to members.

An issue was discovered in Mattermost Mobile Apps before 1.26.0. Cookie data can persist on a device after a logout.

An issue was discovered in Mattermost Server before 5.18.0. It has weak permissions for server-local file storage.

Mattermost fails to perform authorization checks in the /plugins/playbooks/api/v0/runs/add-to-timeline-dialog endpoint of the Playbooks plugin allowing an attacker to get limited information about a post if they know the post ID

An issue was discovered in Mattermost Server before 5.21.0. mmctl allows directory traversal via HTTP, aka MMSA-2020-0014.

An issue was discovered in Mattermost Server before 5.19.0. Attackers can discover private channels via the "get channel by name" API, aka MMSA-2020-0004.

An issue was discovered in Mattermost Mobile Apps before 1.29.0. The iOS app allowed Single Sign-On cookies and Local Storage to remain after a logout, aka MMSA-2020-0013.

An issue was discovered in Mattermost Mobile Apps before 1.31.2 on iOS. Unintended third-party servers could sometimes obtain authorization tokens, aka MMSA-2020-0022.

An issue was discovered in Mattermost Server before 5.20.0. Non-members can receive broadcasted team details via the update_team WebSocket event, aka MMSA-2020-0012.

An issue was discovered in Mattermost Server before 5.18.0, 5.17.2, 5.16.4, 5.15.4, and 5.9.7. There are weak permissions for configuration files.

An issue was discovered in Mattermost Mobile Apps before 1.26.0. Local logging is not blocked for sensitive information (e.g., server addresses or message content).

An issue was discovered in Mattermost Server before 5.12.0. Use of a Proxy HTTP header, rather than the source address in an IP packet header, for obtaining IP address information was mishandled.

An issue was discovered in Mattermost Server before 5.16.1, 5.15.2, 5.14.5, and 5.9.6. It allows attackers to obtain sensitive information (local files) during legacy attachment migration.

An issue was discovered in Mattermost Server before 5.15.0. Login access control can be bypassed via crafted input.

Mattermost fails to normalize UTF confusable characters when determining if a preview should be generated for a hyperlink, allowing an attacker to trigger link preview on a disallowed domain using a specially crafted link.

An issue was discovered in Mattermost Server before 3.0.0. It allows attackers to obtain sensitive information about team URLs via an API.

Mattermost allows an attacker to request a preview of an existing message when creating a new message via the createPost API call, disclosing the contents of the linked message.

Mattermost Boards plugin v0.10.0 and earlier fails to invalidate a session on the server-side when a user logged out of Boards, which allows an attacker to reuse old session token for authorization.

Mattermost 6.0.2 and earlier fails to sufficiently sanitize user's password in audit logs when user creation fails.

Mattermost Desktop App versions <=5.8.0 fail to safeguard screen capture functionality which allows an attacker to silently capture high-quality screenshots via JavaScript APIs.

An issue was discovered in Mattermost Mobile Apps before 1.26.0. A view cache can persist on a device after a logout.

An issue was discovered in Mattermost Server before 5.9.0, 5.8.1, 5.7.3, and 4.10.8. It allows attackers to obtain sensitive information during a role change.

An issue was discovered in Mattermost Server before 5.8.0. It does not always generate a robots.txt file.

An issue was discovered in Mattermost Server before 5.9.0, 5.8.1, 5.7.3, and 4.10.8. It allows attackers to obtain sensitive information about whether someone has 2FA enabled.

Mattermost versions 10.7.x <= 10.7.0, 10.6.x <= 10.6.2, 10.5.x <= 10.5.3, 9.11.x <= 9.11.12 fail to properly validate permissions when changing team privacy settings, allowing team administrators without the 'invite user' permission to access and modify team invite IDs via the /api/v4/teams/:teamId/privacy endpoint.

Mattermost versions 10.x <= 10.2 fail to accurately reflect missing settings, which allows confusion for admins regarding a Calls security-sensitive configuration via incorrect UI reporting.

Mattermost is grouping calls in the /metrics endpoint by id and reports that id in the response. Since this id is the channelID, the public /metrics endpoint is revealing channelIDs.

An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of superfluous authentication credentials.

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

Mattermost versions 9.5.x <= 9.5.5 and 9.8.0 fail to properly sanitize the recipients of a webhook event which allows an attacker monitoring webhook events to retrieve the channel IDs of archived or restored channels.

An issue was discovered in Mattermost Server before 3.0.0. It does not ensure that a cookie is used over SSL.

An issue was discovered in Mattermost Server before 3.2.0. The initial_load API disclosed unnecessary personal information.

A call stack overflow bug in the SAML login feature in Mattermost server in versions up to and including 6.3.2 allows an attacker to crash the server via submitting a maliciously crafted POST body.

An issue was discovered in Mattermost Server before 4.1.0, 4.0.4, and 3.10.3. It allows CSV injection via a compliance report.

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 use  innerText / textContent when setting the channel name in the webapp during autocomplete, allowing an attacker to inject HTML to a victim's page by create a channel name that is valid HTML. No XSS is possible though. 

Mattermost Jira plugin versions shipped with Mattermost versions 8.1.x before 8.1.10, 9.2.x before 9.2.6, 9.3.x before 9.3.2, and 9.4.x before 9.4.3 fail to escape user-controlled outputs when generating HTML pages, which allows an attacker to perform reflected cross-site scripting attacks against the users of the Mattermost server.

Mattermost fails to sanitize code permalinks, allowing an attacker to preview code from private repositories by posting a specially crafted permalink on a channel.

Mattermost webapp fails to validate route parameters in/<TEAM_NAME>/channels/<CHANNEL_NAME> allowing an attacker to perform a client-side path traversal.

Mattermost version 2.10.0 and earlier fails to sanitize deeplink paths, which allows an attacker to perform CSRF attacks against the server.

An issue was discovered in Mattermost Server before 5.1. It allows attackers to cause a denial of service via the invite_people slash command.

beroNet VoIP Gateways before 3.0.16 have a PHP script that allows downloading arbitrary files, including ones with credentials.

Redmine before 4.0.7 and 4.1.x before 4.1.1 allows attackers to discover the subject of a non-visible issue by performing a CSV export and reading time entries.

Redash 8.0.0 is affected by LDAP Injection. There is an information leak through the crafting of special queries, escaping the provided template since the username included in the search filter lacks sanitization.