CVE-2024-39830: mattermost Auth Bypass — Fix

Description

Mattermost versions 9.8.x <= 9.8.0, 9.7.x <= 9.7.4, 9.6.x <= 9.6.2 and 9.5.x <= 9.5.5, when shared channels are enabled, fail to use constant time comparison for remote cluster tokens which allows an attacker to retrieve the remote cluster token via a timing attack during remote cluster token comparison.

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CVSS v3.1 Score

8.1

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-287 Improper Authentication

CWE-203 CWE-203

Affected Products

Vendor	Product	Versions
mattermost	mattermost	9.5.0 — 9.5.6
mattermost	mattermost	9.6.0 — 9.6.3
mattermost	mattermost	9.7.0 — 9.7.5
mattermost	mattermost	9.8.0 — 9.8.1

References

Advisories & Patches

https://mattermost.com/security-updates https://mattermost.com/security-updates

Frequently Asked Questions

What is CVE-2024-39830? +

Mattermost versions 9.8.x <= 9.8.0, 9.7.x <= 9.7.4, 9.6.x <= 9.6.2 and 9.5.x <= 9.5.5, when shared channels are enabled, fail to use constant time comparison for remote cluster tokens which allows an attacker to retrieve the remote cluster token via a timing attack during remote cluster token comparison. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2024-39830? +

CVE-2024-39830 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-39830? +

CVE-2024-39830 affects products from mattermost, specifically: mattermost. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-39830? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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