CVE-2024-39274

Malicious remote can add users to arbitrary teams and channels

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

Remediation

Solution:

  • Update Mattermost to versions 9.10.0, 9.9.1, 9.5.7, 9.7.6, 9.8.2 or higher.

Category

8.7
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.12%
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-2024-39274?
CVE-2024-39274 has been scored as a high severity vulnerability.
How to fix CVE-2024-39274?
To fix CVE-2024-39274: Update Mattermost to versions 9.10.0, 9.9.1, 9.5.7, 9.7.6, 9.8.2 or higher.
Is CVE-2024-39274 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-39274 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-2024-39274?
CVE-2024-39274 affects Mattermost Mattermost.
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