CVE-2023-2808: Lack of URL normalization allows rendering previews for disallowed domains

Published May 29, 2023
·
Updated

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.

Affected Software

3 affected components
Mattermost Mattermost>=5.34.0<7.1.9
Mattermost Mattermost>=7.2.0<7.8.4
Mattermost Mattermost>=7.9.0<7.9.3

Remediation

Information

Update Mattermost to version v7.1.9, v7.8.4, v7.9.3, v7.10, or higher.

Event History

May 29, 2023
CVE Published
via MITRE·09:07 AM
Data Sourced
via MITRE·09:07 AM
RemedyDescriptionSeverityWeakness
Data Sourced
10:15 AM
Description

Frequently Asked Questions

1

What is CVE-2023-2808?

CVE-2023-2808 is a vulnerability in Mattermost that allows an attacker to trigger a link preview on a disallowed domain using a specially crafted link.

2

How does Mattermost fail to normalize UTF confusable characters?

Mattermost fails to normalize UTF confusable characters when determining if a preview should be generated for a hyperlink.

3

What is the severity of CVE-2023-2808?

CVE-2023-2808 has a severity rating of medium (5.3).

4

Which versions of Mattermost are affected by CVE-2023-2808?

Mattermost versions 5.34.0 to 7.1.9, 7.2.0 to 7.8.4, and 7.9.0 to 7.9.3 are affected by CVE-2023-2808.

5

How can the CVE-2023-2808 vulnerability be fixed?

To fix the CVE-2023-2808 vulnerability, it is recommended to update Mattermost to a version that is not affected by the vulnerability.

Contact

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