CVE-2017-18900

CRITICAL

Mattermost Server is vulnerable CSV Injection

Published May 24, 2022Updated February 3, 2026Source: osv

Summary

An issue was discovered in Mattermost Server before 4.0.4 and 3.10.3. It allows CSV injection via a compliance report.

Remediation

Upgrade to the fixed version using your package manager.

Update github.com/mattermost/mattermost-server to 3.10.3 or later

go get github.com/mattermost/mattermost-server@v3.10.3

Update github.com/mattermost/mattermost-server to 4.0.3 or later

go get github.com/mattermost/mattermost-server@v4.0.3

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

Affected Packages (2)

Package	Ecosystem	Affected	Fixed In
github.com/mattermost/mattermost-server	go	All versions	3.10.3
github.com/mattermost/mattermost-server	go	All versions	4.0.3

Vulnerability Classification

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

CWE-1236
View on MITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 9.8 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

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

References

Frequently Asked Questions

What is CVE-2017-18900?: Mattermost Server is vulnerable CSV Injection This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 9.8/10).
How do I check if my project is affected by CVE-2017-18900?: CVE-2017-18900 affects github.com/mattermost/mattermost-server. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2017-18900 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

9.8

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-8q4v-35v6-g8wr

GO-2026-4303

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