CVE-2024-39274: mattermost Access Control Flaw — Fix

Description

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to properly validate that the channel that comes from the sync message is a shared channel, when shared channels are enabled, which allows a malicious remote to add users to arbitrary teams and channels

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CVSS v3.1 Score

8.7

HIGH

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

Weakness Type (CWE)

CWE-284 CWE-284

Affected Products

Vendor	Product	Versions
mattermost	mattermost	9.5.0 — 9.5.7
mattermost	mattermost	9.7.0 — 9.7.6
mattermost	mattermost	9.8.0 — 9.8.2
mattermost	mattermost	All

References

Advisories & Patches

https://mattermost.com/security-updates

Frequently Asked Questions

What is CVE-2024-39274? +

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to properly validate that the channel that comes from the sync message is a shared channel, when shared channels are enabled, which allows a malicious remote to add users to arbitrary teams and channels It has a CVSS v3.1 base score of 8.7 (HIGH).

How severe is CVE-2024-39274? +

CVE-2024-39274 has a CVSS v3.1 score of 8.7 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-39274? +

CVE-2024-39274 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-2024-39274? +

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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