Improper Authentication in NordVPN

1) Improper Authentication

EUVDB-ID: #VU37357

Risk: High

CVSSv3.1: 7.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-9105

CWE-ID: CWE-287 - Improper Authentication

Exploit availability: No

Description

The vulnerability allows a remote authenticated user to execute arbitrary code.

NordVPN 3.3.10 for macOS suffers from a root privilege escalation vulnerability. The vulnerability stems from its privileged helper tool's implemented XPC service. This XPC service is responsible for receiving and processing new OpenVPN connection requests from the main application. Unfortunately this XPC service is not protected, which allows arbitrary applications to connect and send it XPC messages. An attacker can send a crafted XPC message to the privileged helper tool requesting it make a new OpenVPN connection. Because he or she controls the contents of the XPC message, the attacker can specify the location of the openvpn executable, which could point to something malicious they control located on disk. Without validation of the openvpn executable, this will give the attacker code execution in the context of the privileged helper tool.

Mitigation

Install update from vendor's website.

Vulnerable software versions

NordVPN: 3.3.10

External links

http://exchange.xforce.ibmcloud.com/vulnerabilities/140939
http://github.com/VerSprite/research/blob/master/advisories/VS-2018-015.md

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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