CVE-2024-39777

CRITICAL

Mattermost allows unsolicited invites to expose access to local channels

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 disallow unsolicited invites to expose access to local channels, when shared channels are enabled, which allows a malicious remote to send an invite with the ID of an existing local channel, and that local channel will then become shared without the consent of the local admin.

Remediation

Upgrade to the fixed version using your package manager.

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 9.8.1 or later

go get github.com/mattermost/mattermost/server/v8@v9.8.1

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	9.9.1
github.com/mattermost/mattermost/server/v8	go	All versions	9.8.1
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

https://nvd.nist.gov/vuln/detail/CVE-2024-39777
ADVISORY
https://github.com/mattermost/mattermost
PACKAGE
https://mattermost.com/security-updates
WEB

Frequently Asked Questions

What is CVE-2024-39777?: Mattermost allows unsolicited invites to expose access to local channels 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-2024-39777?: CVE-2024-39777 affects github.com/mattermost/mattermost/server/v8. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2024-39777 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-q22q-2rrf-m27p

GO-2024-3092

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