TI-2017-14037 Aliases CVE-2017-18889 GHSA-jp57-4x34-5v94

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2.

LOW 21CWE-20Published 2020-06-19 · Updated 2024-08-05

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: None · Low · None
Fix status: Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub.

Summary

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. An attacker could create fictive system-message posts via webhooks and slash commands, in the v3 or v4 REST API.

Why it matters now

EPSS 0.00669 52nd percentileScored 2026-11-07

Fix Fixed github.com/mattermost/mattermost-server (Go): 4.1.2, 4.2.1, 4.3.0

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA
—	github.com/mattermost/mattermost-server (Go)	before 4.1.2	4.1.2	Patch available	GHSA-jp57-4x34-5v94
—	github.com/mattermost/mattermost-server (Go)	4.2.0-rc1 to before 4.2.1	4.2.1	Patch available	GHSA-jp57-4x34-5v94
—	github.com/mattermost/mattermost-server (Go)	4.3.0-rc1 to before 4.3.0	4.3.0	Patch available	GHSA-jp57-4x34-5v94

— Vendor— Affected all versions Fixed in — No fix listed CNA
github.com/mattermost/mattermost-server (Go) Vendor— Affected before 4.1.2 Fixed in 4.1.2 Patch available GHSA-jp57-4x34-5v94
github.com/mattermost/mattermost-server (Go) Vendor— Affected 4.2.0-rc1 to before 4.2.1 Fixed in 4.2.1 Patch available GHSA-jp57-4x34-5v94
github.com/mattermost/mattermost-server (Go) Vendor— Affected 4.3.0-rc1 to before 4.3.0 Fixed in 4.3.0 Patch available GHSA-jp57-4x34-5v94

CPE configurations NVD · 5

CPE	Versions	Role	Vendor
cpe:2.3:a:mattermost:mattermost_server::::::::	before 4.1.2; 4.2.0 to before 4.2.1	Vulnerable	Mattermost
cpe:2.3:a:mattermost:mattermost_server:4.3.0:rc1::::::	4.3.0 rc1	Vulnerable	Mattermost
cpe:2.3:a:mattermost:mattermost_server:4.3.0:rc2::::::	4.3.0 rc2	Vulnerable	Mattermost
cpe:2.3:a:mattermost:mattermost_server:4.3.0:rc3::::::	4.3.0 rc3	Vulnerable	Mattermost
cpe:2.3:a:mattermost:mattermost_server:4.3.0:rc4::::::	4.3.0 rc4	Vulnerable	Mattermost

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions before 4.1.2; 4.2.0 to before 4.2.1 Vulnerable ·Mattermost
cpe:2.3:a:mattermost:mattermost_server:4.3.0:rc1:*:*:*:*:*:* Versions 4.3.0 rc1 Vulnerable ·Mattermost
cpe:2.3:a:mattermost:mattermost_server:4.3.0:rc2:*:*:*:*:*:* Versions 4.3.0 rc2 Vulnerable ·Mattermost
cpe:2.3:a:mattermost:mattermost_server:4.3.0:rc3:*:*:*:*:*:* Versions 4.3.0 rc3 Vulnerable ·Mattermost
cpe:2.3:a:mattermost:mattermost_server:4.3.0:rc4:*:*:*:*:*:* Versions 4.3.0 rc4 Vulnerable ·Mattermost

Remediation

Fix · GHSA-jp57-4x34-5v94 github.com/mattermost/mattermost-server (Go) Fixed in 4.1.2 Advisory →
Fix · GHSA-jp57-4x34-5v94 github.com/mattermost/mattermost-server (Go) Fixed in 4.2.1 Advisory →
Fix · GHSA-jp57-4x34-5v94 github.com/mattermost/mattermost-server (Go) Fixed in 4.3.0 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2017-18889
2026-10-03 Alias added: GHSA-jp57-4x34-5v94

References

Advisory 2

Other 2

TI-2025-18933 Arbitrary file read in Mattermost Boards via import & export board archive CVSS 3.1CRITICAL 9.9
TI-2025-04465 Path Traversal Leading to RCE by Any Authenticated Mattermost User CVSS 3.1CRITICAL 9.9
TI-2017-14068 An issue was discovered in Mattermost Server before 3.6.2. CVSS 3.1CRITICAL 9.8
TI-2017-14060 An issue was discovered in Mattermost Server before 3.8.2, 3.7.5, and 3.6.7. CVSS 3.1CRITICAL 9.8
TI-2017-14048 An issue was discovered in Mattermost Server before 4.1.0, 4.0.4, and 3.10.3. CVSS 3.1CRITICAL 9.8
TI-2025-14360 Arbitrary file read via block duplication in Mattermost Boards CVSS 3.1CRITICAL 9.9

See all 505 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences