SB2020061953 - Multiple vulnerabilities in Mattermost, Mattermost Server



SB2020061953 - Multiple vulnerabilities in Mattermost, Mattermost Server

Published: June 19, 2020 Updated: August 8, 2020

Security Bulletin ID SB2020061953
Severity
Medium
Patch available
YES
Number of vulnerabilities 5
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 40% Low 60%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 5 secuirty vulnerabilities.


1) Incorrect permission assignment for critical resource (CVE-ID: CVE-2018-21256)

The vulnerability allows a remote authenticated user to manipulate data.

An issue was discovered in Mattermost Server before 5.1. It allows attackers to bypass intended access restrictions (for group-message channel creation) via the Group message slash command.


2) Incorrect permission assignment for critical resource (CVE-ID: CVE-2018-21254)

The vulnerability allows a remote authenticated user to manipulate data.

An issue was discovered in Mattermost Server before 5.1. An attacker can bypass intended access control (for direct-message channel creation) via the Message slash command.


3) Incorrect permission assignment for critical resource (CVE-ID: CVE-2018-21255)

The vulnerability allows a remote authenticated user to manipulate data.

An issue was discovered in Mattermost Server before 5.1. Non-members of a channel could use the Channel PATCH API to modify that channel.


4) Missing Authorization (CVE-ID: CVE-2018-21257)

The vulnerability allows a remote non-authenticated attacker to manipulate data.

An issue was discovered in Mattermost Server before 5.1. It allows attackers to bypass intended access restrictions (for setting a channel header) via the Channel header slash command API.


5) Improper Neutralization of Special Elements in Output Used by a Downstream Component (CVE-ID: CVE-2018-21258)

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

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.


Remediation

Install update from vendor's website.