CVE-2023-2808

Lack of URL normalization allows rendering previews for disallowed domains

Description

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.

Remediation

Solution:

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

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.17%
Vendor Advisory mattermost.com
Affected: Mattermost Mattermost
Published at:
Updated at:

References

Link Tags
https://mattermost.com/security-updates/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2023-2808?
CVE-2023-2808 has been scored as a medium severity vulnerability.
How to fix CVE-2023-2808?
To fix CVE-2023-2808: Update Mattermost to version v7.1.9, v7.8.4, v7.9.3, v7.10, or higher.
Is CVE-2023-2808 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-2808 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-2808?
CVE-2023-2808 affects Mattermost Mattermost.
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