MEDIUM · 4.8

CVE-2020-3442

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 DuoConne...

Vulnerability Description

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.

CVSS Score

4.8

MEDIUM

CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
Attack Vector
ADJACENT_NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE

Affected Products

VendorProductVersions
DuoDuoconnect< 1.1.1

Related Weaknesses (CWE)

References

FAQ

What is CVE-2020-3442?

CVE-2020-3442 is a vulnerability with a CVSS score of 4.8 (MEDIUM). 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 DuoConne...

How severe is CVE-2020-3442?

CVE-2020-3442 has been rated MEDIUM with a CVSS base score of 4.8/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2020-3442?

Check the references section above for vendor advisories and patch information. Affected products include: Duo Duoconnect.