CVE-2020-5763 : Security Advisory and Response

Grandstream HT800 series firmware version 1.0.17.5 and below contain a backdoor in the SSH service, allowing an authenticated remote attacker to obtain a root shell.

Understanding CVE-2020-5763

This CVE involves a critical vulnerability in the Grandstream HT800 Series firmware.

What is CVE-2020-5763?

The CVE-2020-5763 vulnerability pertains to a backdoor present in the SSH service of Grandstream HT800 series firmware versions 1.0.17.5 and earlier. This security flaw enables a remote attacker to gain root shell access by correctly responding to a challenge prompt.

The Impact of CVE-2020-5763

The exploitation of this vulnerability can lead to unauthorized access and control of affected devices, posing a significant security risk to users and organizations.

Technical Details of CVE-2020-5763

This section provides more in-depth technical insights into the CVE.

Vulnerability Description

The backdoor in the SSH service of Grandstream HT800 series firmware versions 1.0.17.5 and below allows authenticated remote attackers to achieve root shell access by answering a challenge prompt.

Affected Systems and Versions

Product: Grandstream HT800 Series
Vendor: n/a
Versions Affected: 1.0.17.5 and below

Exploitation Mechanism

The vulnerability can be exploited by an authenticated remote attacker who correctly responds to a challenge prompt, gaining root shell access.

Mitigation and Prevention

Protecting systems from CVE-2020-5763 requires immediate action and long-term security measures.

Immediate Steps to Take

Update the firmware to a secure version that addresses the backdoor issue.
Monitor network traffic for any suspicious activity that may indicate exploitation attempts.

Long-Term Security Practices

Implement strong authentication mechanisms to prevent unauthorized access.
Regularly audit and review system configurations to identify and mitigate security weaknesses.

Patching and Updates

Apply patches and updates provided by Grandstream promptly to eliminate the backdoor vulnerability and enhance system security.