DuoConnect Client cleartext transmission

Summaryinfo

A vulnerability was found in DuoConnect Client. It has been declared as problematic. The impacted element is an unknown function. Executing a manipulation can lead to cleartext transmission. This vulnerability is handled as CVE-2020-3442. The attack can only be done within the local network. There is not any exploit available.

Detailsinfo

A vulnerability has been found in DuoConnect Client (version now known) and classified as problematic. This vulnerability affects some unknown processing. The manipulation with an unknown input leads to a cleartext transmission vulnerability. The CWE definition for the vulnerability is CWE-319. The product transmits sensitive or security-critical data in cleartext in a communication channel that can be sniffed by unauthorized actors. As an impact it is known to affect confidentiality. CVE summarizes:

The DuoConnect client enables users to establish SSH connections to hosts protected by a DNG instance. When a user initiates an SSH connection to a DNG-protected host for the first time using DuoConnect, the user’s browser is opened to a login screen in order to complete authentication determined by the contents of the '-relay' argument. If the ‘-relay’ is set to a URL beginning with "http://", then the browser will initially attempt to load the URL over an insecure HTTP connection, before being immediately redirected to HTTPS (in addition to standard redirect mechanisms, the DNG uses HTTP Strict Transport Security headers to enforce this). After successfully authenticating to a DNG, DuoConnect stores an authentication token in a local system cache, so users do not have to complete this browser-based authentication workflow for every subsequent SSH connection. These tokens are valid for a configurable period of time, which defaults to 8 hours. If a user running DuoConnect already has a valid token, then instead of opening a web browser, DuoConnect directly contacts the DNG, again using the configured '-relay' value, and sends this token, as well as the intended SSH server hostname and port numbers. If the '-relay' argument begins with "http://", then this request will be sent over an insecure connection, and could be exposed to an attacker who is sniffing the traffic on the same network. The DNG authentication tokens that may be exposed during SSH relay may be used to gain network-level access to the servers and ports protected by that given relay host. The DNG provides network-level access only to the protected SSH servers. It does not interact with the independent SSH authentication and encryption. An attacker cannot use a stolen token on its own to authenticate against a DNG-protected SSH server.

The weakness was released 07/20/2020 (Website). The advisory is shared for download at duo.com. This vulnerability was named CVE-2020-3442 since 12/12/2019. The exploitation appears to be difficult. Access to the local network is required for this attack to succeed. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1040.

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

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• DuoConnect Client

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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