CVE-2017-20204: DBLTek GoIP Telnet Admin Interface Undocumented Backdoor
DBLTek GoIP devices (models GoIP 1, 4, 8, 16, and 32) contain an undocumented vendor backdoor in the Telnet administrative interface that allows remote authentication as an undocumented user via a proprietary challenge–response scheme which is fundamentally flawed. Because the challenge response can be computed from the challenge itself, a remote attacker can authenticate without knowledge of a secret and obtain a root shell on the device. This can lead to persistent remote code execution, full device compromise, and arbitrary control of the device and any managed services. The firmware used within these devices was updated in December 2016 to make this vulnerability more complex to exploit. However, it is unknown if DBLTek has taken steps to fully mitigate.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2017-20204?
CVE-2017-20204 is classified as a high severity vulnerability due to the presence of an undocumented backdoor in DBLTek GoIP devices.
How do I fix CVE-2017-20204?
To mitigate CVE-2017-20204, it is recommended to disable the Telnet interface or apply firmware updates from DBLTek that address this vulnerability.
What devices are affected by CVE-2017-20204?
CVE-2017-20204 affects the DBLTek GoIP series including models 1, 4, 8, 16, and 32.
What is the nature of the backdoor in CVE-2017-20204?
The backdoor in CVE-2017-20204 allows for remote authentication on the Telnet administrative interface through a flawed proprietary challenge-response mechanism.
Is there a known exploit for CVE-2017-20204?
Yes, there are known exploitation methods for CVE-2017-20204 that take advantage of the undocumented backdoor in affected GoIP devices.