OpenVPN up to 2.4.5 Management Interface format string ⚔ [Disputed]

Summaryinfo

A vulnerability was found in OpenVPN up to 2.4.5 and classified as problematic. Affected by this issue is some unknown functionality of the component Management Interface. The manipulation results in format string. This vulnerability is known as CVE-2018-7544. It is possible to launch the attack remotely. No exploit is available. There are still doubts about whether this vulnerability truly exists.

Detailsinfo

A vulnerability was found in OpenVPN up to 2.4.5 (Network Encryption Software). It has been classified as problematic. Affected is an unknown code of the component Management Interface. The manipulation with an unknown input leads to a format string vulnerability. CWE is classifying the issue as CWE-134. The product uses a function that accepts a format string as an argument, but the format string originates from an external source. This is going to have an impact on confidentiality. CVE summarizes:

** DISPUTED ** A cross-protocol scripting issue was discovered in the management interface in OpenVPN through 2.4.5. When this interface is enabled over TCP without a password, and when no other clients are connected to this interface, attackers can execute arbitrary management commands, obtain sensitive information, or cause a denial of service (SIGTERM) by triggering XMLHttpRequest actions in a web browser. This is demonstrated by a multipart/form-data POST to http://localhost:23000 with a "signal SIGTERM" command in a TEXTAREA element. NOTE: The vendor disputes that this is a vulnerability. They state that this is the result of improper configuration of the OpenVPN instance rather than an intrinsic vulnerability, and now more explicitly warn against such configurations in both the management-interface documentation, and with a runtime warning.

The weakness was published 03/16/2018 (Website). The advisory is shared for download at blog.0xlabs.com. This vulnerability is traded as CVE-2018-7544 since 02/27/2018. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available.

The real existence of this vulnerability is still doubted at the moment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

• Network Encryption Software

Name

• OpenVPN

Version

• 2.4.0
• 2.4.1
• 2.4.2
• 2.4.3
• 2.4.4
• 2.4.5

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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