Mattermost Server is vulnerable to DoS through maliciously crafted posts

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. It allows crafted posts that potentially cause a web browser to hang...

Mattermost Server has intermittent Authorization bypass for resource-owners

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5, when used as an OAuth 2.0 service provider. Resource-owner authorization can be intermittently bypassed, allowing account takeover...

GHSA-F7C3-7VP3-44P6 Mattermost Server mishandles redirect denial action

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5, when used as an OAuth 2.0 service provider. It mishandles a deny action for a redirection...

GHSA-H742-XX59-R9PQ Mattermost Server exposes sensitive user status information via REST API version 4 endpoint

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...

GHSA-WJ5W-QGHH-GVQP Mattermost Server does not neutralize HTML content in an Email template field

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. E-mail templates can have a field in which HTML content is not neutralized...

GHSA-63WG-QMRV-7Q66 Mattermost Server allows attackers to log sensitive information via DEBUG REST API logging endpoint

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. It allows attackers to add DEBUG lines to the logs via a REST API version 3 logging endpoint...

Mattermost Server allows attackers to create buttons that can launch API requests

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows an attacker to create a button that, when pressed by a user, launches an API request...

Mattermost Server is vulnerable to XSS through display name field

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. Display names allow XSS...

GHSA-WVJG-33P9-938H Mattermost Server does not properly restrict use of slash commands

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows a bypass of restrictions on use of slash commands...

GHSA-G78F-6XQ7-RRHQ Mattermost Server allows attackers to gain privileges by accessing unintended API endpoints with users' credentials

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows attackers to gain privileges by accessing unintended API endpoints on a user's behalf...

Mattermost Server allows attackers to gain privileges by accessing unintended API endpoints with users' credentials

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows attackers to gain privileges by accessing unintended API endpoints on a user's behalf...

GHSA-876J-JFQF-M7J7 Mattermost Server exposes OAuth personal access tokens to attackers

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows attackers to gain privileges by using a registered OAuth application with personal access tokens...

Mattermost Server exposes OAuth personal access tokens to attackers

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows attackers to gain privileges by using a registered OAuth application with personal access tokens...

Mattermost Server does not properly restrict use of slash commands

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows a bypass of restrictions on use of slash commands...

GHSA-35C4-5QFP-WXJ6 Mattermost Server exposes team creator's e-mail address to other members

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...

GHSA-9RR5-Q43R-CCV4 Mattermost Server does not prevent System Admin from arbitrary file creation

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2 when local storage for files is used. A System Admin can create arbitrary files...

GHSA-X6MW-HF2J-VQPC Mattermost Server is vulnerable to channel invisibility DoS via misformatted post

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows attackers to cause a denial of service channel invisibility via a misformated post...

Mattermost Server does not prevent System Admin from arbitrary file creation

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2 when local storage for files is used. A System Admin can create arbitrary files...

Mattermost Server allows users with a session ID to revoke another users' session

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. Knowledge of a session ID allows revoking another user's session...

GHSA-HJQH-J6RJ-GH8Q Mattermost Server is vulnerable to Path Traversal when files are stored locally

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2 when local storage for files is used. A System Admin can test for the existence of an arbitrary file...