CVE-2021-20859 : Exploit Details and Defense Strategies

ELECOM LAN routers by ELECOM CO.,LTD. with specific firmware versions are vulnerable to OS Command Injection, allowing an attacker to run arbitrary OS commands.

Understanding CVE-2021-20859

This CVE identifies a critical vulnerability in ELECOM LAN routers that can be exploited by a network-adjacent authenticated attacker to execute unauthorized OS commands.

What is CVE-2021-20859?

The CVE-2021-20859 vulnerability affects ELECOM LAN routers with firmware versions prior to specific releases. It enables an attacker to execute arbitrary OS commands through unspecified vectors.

The Impact of CVE-2021-20859

This vulnerability poses a significant risk as it allows attackers to gain unauthorized access to the affected routers, potentially leading to further malicious activities and network compromise.

Technical Details of CVE-2021-20859

The following technical information is crucial in understanding the CVE-2021-20859 vulnerability.

Vulnerability Description

The vulnerability in ELECOM LAN routers permits a network-adjacent authenticated attacker to execute unauthorized OS commands through unspecified vectors.

Affected Systems and Versions

ELECOM LAN routers are impacted by this vulnerability, specifically the models with the following firmware versions: WRC-1167GST2, WRC-1167GST2A, WRC-1167GST2H, WRC-2533GS2-B, WRC-2533GS2-W, WRC-1750GS, WRC-1750GSV, WRC-1900GST, WRC-2533GST, WRC-2533GSTA, WRC-2533GST2, WRC-2533GST2SP, WRC-2533GST2-G, and EDWRC-2533GST2, all with firmware versions prior to specified releases.

Exploitation Mechanism

The vulnerability can be exploited by a network-adjacent authenticated attacker with the ability to bypass security measures and inject malicious OS commands into the system.

Mitigation and Prevention

To address the CVE-2021-20859 vulnerability, immediate actions and long-term security practices are essential.

Immediate Steps to Take

It is recommended to update the firmware of ELECOM LAN routers to the latest version provided by the vendor and implement strong network segmentation to limit attacker access.

Long-Term Security Practices

Regularly monitor network traffic, conduct security assessments, and train employees on cybersecurity best practices to enhance overall network security.

Patching and Updates

Stay informed about security advisories from ELECOM CO.,LTD., and apply patches promptly to eliminate vulnerabilities and strengthen router security.