CVE-2024-39274

CRITICAL

Mattermost failed to properly validate that the channel that comes from the sync message is a shared channel

Published August 1, 2024Updated November 18, 2024Source: osv

Summary

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

Upgrade to the fixed version using your package manager.

Update github.com/mattermost/mattermost/server/v8 to 9.8.2 or later

go get github.com/mattermost/mattermost/server/v8@v9.8.2

Update github.com/mattermost/mattermost/server/v8 to 9.9.1 or later

go get github.com/mattermost/mattermost/server/v8@v9.9.1

Update github.com/mattermost/mattermost/server/v8 to 9.5.7 or later

go get github.com/mattermost/mattermost/server/v8@v9.5.7

Update github.com/mattermost/mattermost/server/v8 to 9.7.6 or later

go get github.com/mattermost/mattermost/server/v8@v9.7.6

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (4)

Package	Ecosystem	Affected	Fixed In
github.com/mattermost/mattermost/server/v8	go	All versions	9.8.2
github.com/mattermost/mattermost/server/v8	go	9.9.0	9.9.1
github.com/mattermost/mattermost/server/v8	go	All versions	9.5.7
github.com/mattermost/mattermost/server/v8	go	All versions	9.7.6

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-284
View on MITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 8.7 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None

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

References

Frequently Asked Questions

What is CVE-2024-39274?: Mattermost failed to properly validate that the channel that comes from the sync message is a shared channel This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 8.7/10).
How do I check if my project is affected by CVE-2024-39274?: CVE-2024-39274 affects github.com/mattermost/mattermost/server/v8. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2024-39274 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

8.7

High exploitability or significant impact. Prioritize remediation within days.

Also Known As

GHSA-cmc8-222c-vqp9

GO-2024-3028

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