CVE-2021-1244 : Exploit Details and Defense Strategies

Cisco IOS XR Software for Cisco 8000 Series Routers and Network Convergence System 540 Series Routers Image Verification Vulnerabilities were discovered on February 3, 2021. The vulnerabilities could allow an attacker to execute unsigned code during the boot process on affected devices.

Understanding CVE-2021-1244

This CVE involves multiple vulnerabilities in Cisco Network Convergence System (NCS) 540 Series Routers and Cisco IOS XR Software for Cisco 8000 Series Routers when running specific software images.

What is CVE-2021-1244?

The CVE-2021-1244 involves potential code execution by an authenticated, local attacker during the boot process on affected devices.

The Impact of CVE-2021-1244

The vulnerabilities pose a significant risk, with a CVSSv3.1 base score of 6.7 (Medium severity). They could allow an attacker to compromise confidentiality, integrity, and availability on the affected systems.

Technical Details of CVE-2021-1244

These technical details provide insight into the vulnerability, affected systems, and how an exploit can be carried out.

Vulnerability Description

The vulnerabilities in Cisco IOS XR Software and Cisco 8000 Series Routers could enable an attacker to execute unsigned code locally during the boot process.

Affected Systems and Versions

Cisco IOS XR NCS540L software images, and Cisco IOS XR Software for the Cisco 8000 Series Routers are affected by this vulnerability.

Exploitation Mechanism

An authenticated, local attacker can take advantage of the vulnerability to execute unsigned code during the boot process on the affected devices.

Mitigation and Prevention

To address CVE-2021-1244, users should consider immediate steps and long-term security practices while ensuring timely patching and updates.

Immediate Steps to Take

Implement access controls, restrict unauthorized access, and monitor for any suspicious activity on the network.

Long-Term Security Practices

Regularly update software, follow best security practices, conduct security assessments, and stay informed about potential vulnerabilities.

Patching and Updates

Apply security patches provided by Cisco promptly to mitigate the risk associated with these vulnerabilities.