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CVE-2024-39777 — Vulnerability in...

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.

Advisory Timeline

  • First published August 1, 2024 (802 days ago).
  • Last revised November 18, 2024 — 109 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

Go
Update github.com/mattermost/mattermost/server/v8 to 9.9.1 or later
go get github.com/mattermost/mattermost/server/v8@v9.9.1
Go
Update github.com/mattermost/mattermost/server/v8 to 9.8.1 or later
go get github.com/mattermost/mattermost/server/v8@v9.8.1
Go
Update github.com/mattermost/mattermost/server/v8 to 9.5.7 or later
go get github.com/mattermost/mattermost/server/v8@v9.5.7
Go
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)

Affects 1 ecosystem: go (1).

PackageEcosystemAffectedFixed In
github.com/mattermost/mattermost/server/v8
go
All versions9.9.1
github.com/mattermost/mattermost/server/v8
go
All versions9.8.1
github.com/mattermost/mattermost/server/v8
go
All versions9.5.7
github.com/mattermost/mattermost/server/v8
go
All versions9.7.6

Vulnerability Classification

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

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-2024-39777?
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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  • CVE-2024-39274
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  • CVE-2025-58073
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  • CVE-2026-6961
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  • CVE-2026-6346
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