CVE-2025-4981

CRITICAL

Mattermost allows authenticated users to write files to arbitrary locations

Published June 20, 2025Updated July 28, 2025Source: osv

Summary

Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to sanitize filenames in the archive extractor which allows authenticated users to write files to arbitrary locations on the filesystem via uploading archives with path traversal sequences in filenames, potentially leading to remote code execution. The vulnerability impacts instances where file uploads and document search by content is enabled (FileSettings.EnableFileAttachments = true and FileSettings.ExtractContent = true). These configuration settings are enabled by default.

Remediation

Upgrade to the fixed version using your package manager.

Update github.com/mattermost/mattermost/server/v8 to 9.11.16 or later

go get github.com/mattermost/mattermost/server/v8@v9.11.16

Update github.com/mattermost/mattermost/server/v8 to 10.6.6 or later

go get github.com/mattermost/mattermost/server/v8@v10.6.6

Update github.com/mattermost/mattermost/server/v8 to 10.7.3 or later

go get github.com/mattermost/mattermost/server/v8@v10.7.3

Update github.com/mattermost/mattermost-server to 0.0.0-20250519205859-65aec10162f6 or later

go get github.com/mattermost/mattermost-server@v0.0.0-20250519205859-65aec10162f6

Update github.com/mattermost/mattermost/server/v8 to 8.0.0-20250519205859-65aec10162f6 or later

go get github.com/mattermost/mattermost/server/v8@v8.0.0-20250519205859-65aec10162f6

Update github.com/mattermost/mattermost/server/v8 to 10.8.1 or later

go get github.com/mattermost/mattermost/server/v8@v10.8.1

Update github.com/mattermost/mattermost/server/v8 to 10.5.6 or later

go get github.com/mattermost/mattermost/server/v8@v10.5.6

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

Affected Packages (7)

Package	Ecosystem	Affected	Fixed In
github.com/mattermost/mattermost/server/v8	go	All versions	9.11.16
github.com/mattermost/mattermost/server/v8	go	All versions	10.6.6
github.com/mattermost/mattermost/server/v8	go	All versions	10.7.3
github.com/mattermost/mattermost-server	go	All versions	0.0.0-20250519205859-65aec10162f6
github.com/mattermost/mattermost/server/v8	go	All versions	8.0.0-20250519205859-65aec10162f6
github.com/mattermost/mattermost/server/v8	go	10.8.0	10.8.1
github.com/mattermost/mattermost/server/v8	go	All versions	10.5.6

Vulnerability Classification

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

CWE-427
View on MITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 9.9 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

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

References

Frequently Asked Questions

What is CVE-2025-4981?: Mattermost allows authenticated users to write files to arbitrary locations This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 9.9/10).
How do I check if my project is affected by CVE-2025-4981?: CVE-2025-4981 affects github.com/mattermost/mattermost/server/v8 and github.com/mattermost/mattermost-server. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2025-4981 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

9.9

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-qh58-9v3j-wcjc

GO-2025-3769

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