VU#304455: Authentication Bypass in Tenda N300 Wireless N VDSL2 Modem Router

Overview

An authentication bypass vulnerability exists in the N300 Wireless N VDSL2 Modem Router manufactured by Tenda. This vulnerability allows a remote, unauthenticated user to access sensitive information.

Description

CVE-2023-4498 is an authentication bypass vulnerability that enables an unauthenticated attacker who has access to the web console, either locally or remotely, to access resources that would normally be protected. The attacker can construct a web request that includes a white-listed keyword in the path, causing the URL to be served directly (rather than blocked or challenged with an authentication prompt).

Impact

Successful exploitation of this vulnerability could grant the attacker access to pages that would otherwise require authentication. An unauthenticated attacker could thereby gain access to sensitive information, such as the Administrative password, which could be used to launch additional attacks.

Solution

There is no known solution to the vulnerability. Always update your router to the latest available firmware version. Disabling both the remote (WAN-side) administration services and the web interface on the WAN on any SoHo router is also recommended.

Acknowledgements

Thanks to the reporter from the Spike Reply Cybersecurity Team. This document was written by Timur Snoke.

Vendor Information

References

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-4498