CVE-2021-27139 : Exploit Details and Defense Strategies

This article provides an overview of CVE-2021-27139, a vulnerability found in FiberHome HG6245D devices through RP2613 allowing unauthorized information extraction without authentication.

Understanding CVE-2021-27139

CVE-2021-27139 is a security issue impacting FiberHome HG6245D devices through RP2613, enabling attackers to access device information without the need for authentication.

What is CVE-2021-27139?

The vulnerability in FiberHome HG6245D devices allows threat actors to extract sensitive data by bypassing authentication through the manipulation of JavaScript and visiting specific URLs.

The Impact of CVE-2021-27139

This security flaw poses a significant risk as it compromises the confidentiality of device information and opens the door for unauthorized access to sensitive data stored on the affected devices.

Technical Details of CVE-2021-27139

The following are the key technical details related to CVE-2021-27139:

Vulnerability Description

The flaw on FiberHome HG6245D devices enables attackers to obtain information without the need for valid credentials by exploiting certain web functionalities.

Affected Systems and Versions

All FiberHome HG6245D devices running RP2613 are susceptible to this vulnerability, regardless of specific product or version.

Exploitation Mechanism

By disabling JavaScript and accessing the /info.asp URL, threat actors can extract data from the device without being authenticated, highlighting a critical security oversight.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-27139, consider the following steps:

Immediate Steps to Take

Disable access to sensitive URLs like /info.asp to prevent unauthorized data extraction.
Implement network segmentation to limit exposure of vulnerable devices.

Long-Term Security Practices

Regularly update device firmware to patch known security vulnerabilities.
Conduct security assessments and penetration testing to identify and address potential weaknesses.

Patching and Updates

Refer to the vendor's official security advisories and release notes to apply relevant patches and updates to address the CVE-2021-27139 vulnerability.