Vulnerability identifier: #VU34209

Vulnerability risk: High

CVSSv3.1: 8.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-18920

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mattermost Server
Client/Desktop applications / Messaging software

Vendor: Mattermost, Inc.

Description

The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.

An issue was discovered in Mattermost Server before 3.6.2. The WebSocket feature does not follow the Same Origin Policy.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Mattermost Server: 3.6.0 - 3.6.1

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External links
http://mattermost.com/security-updates/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.