CVE-2021-21743 : Security Advisory and Response

This article provides detailed information about CVE-2021-21743, a CRLF injection vulnerability in the ZTE MF971R product that could be exploited by attackers to manipulate HTTP response header information.

Understanding CVE-2021-21743

This section delves into the vulnerability and its impact.

What is CVE-2021-21743?

The CVE-2021-21743 vulnerability exists in the ZTE MF971R product, allowing attackers to alter HTTP response headers using a crafted HTTP request.

The Impact of CVE-2021-21743

The vulnerability enables threat actors to potentially modify HTTP response headers, leading to various security risks and potential attacks.

Technical Details of CVE-2021-21743

This section explores the specifics of the vulnerability.

Vulnerability Description

The flaw in ZTE MF971R permits CRLF injection, which, if exploited, allows unauthorized alteration of HTTP responses.

Affected Systems and Versions

The affected product versions include BD_ZTE_MF971RV1.0.0B05, BD_PLKPLMF971R1V1.0.0B06, BD_MF971R2V1.0.0B03, BD_ZTE_MF971RS2V1.0.0B03, and BD_ZTE_MF971RSV1.0.0B05.

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specially crafted HTTP requests to manipulate HTTP response headers.

Mitigation and Prevention

This section focuses on mitigating the risks associated with CVE-2021-21743.

Immediate Steps to Take

Organizations should apply security patches promptly and monitor network traffic for any signs of exploitation.

Long-Term Security Practices

Implementing secure coding practices, regular security audits, and educating staff on potential threats can enhance long-term security.

Patching and Updates

Vendors may release security patches to address the vulnerability, and users are advised to update their ZTE MF971R devices with the latest patches.