CVE-2019-20871: High severity mattermost vulnerability

Published Jun 19, 2020
·
Updated

An issue was discovered in Mattermost Server before 5.9.0, 5.8.1, 5.7.3, and 4.10.8. The Markdown library allows catastrophic backtracking.

Affected Software

7 affected components
Mattermost Mattermost Server<4.10.8
Mattermost Mattermost Server>=5.7.0<5.7.3
Mattermost Mattermost Server>=5.8.0<5.8.1
Mattermost Mattermost Server=5.9.0-rc1
Mattermost Mattermost Server=5.9.0-rc2
Mattermost Mattermost Server=5.9.0-rc3
Mattermost Mattermost Server=5.9.0-rc4

Event History

Jun 19, 2020
CVE Published
via MITRE·03:22 PM
Data Sourced
via MITRE·03:22 PM
Description

Frequently Asked Questions

1

What is the severity of CVE-2019-20871?

CVE-2019-20871 is classified as a medium to high severity vulnerability due to its potential for denial of service through catastrophic backtracking.

2

How do I fix CVE-2019-20871?

To fix CVE-2019-20871, upgrade to Mattermost Server version 5.9.0 or later, or apply the relevant patches provided by Mattermost.

3

What versions of Mattermost are affected by CVE-2019-20871?

Mattermost Server versions prior to 5.9.0, 5.8.1, 5.7.3, and 4.10.8 are affected by CVE-2019-20871.

4

What type of vulnerability is CVE-2019-20871?

CVE-2019-20871 is a denial of service vulnerability related to the Markdown library used in Mattermost Server.

5

Is there a workaround for CVE-2019-20871?

While the best course of action is to upgrade, you may review your instance's configurations, though there are no officially recommended workarounds for this vulnerability.

Contact

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