CVE-2021-1619 : Exploit Details and Defense Strategies

A vulnerability in the authentication, authorization, and accounting (AAA) function of Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass NETCONF or RESTCONF authentication and perform unauthorized actions or cause denial of service.

Understanding CVE-2021-1619

This article delves into the impact, technical details, and mitigation strategies concerning CVE-2021-1619.

What is CVE-2021-1619?

CVE-2021-1619 highlights a flaw in Cisco IOS XE Software that permits unauthenticated attackers to bypass NETCONF or RESTCONF authentication and potentially manipulate device configurations or initiate denial of service attacks.

The Impact of CVE-2021-1619

With a CVSSv3.1 base score of 9.8 (Critical), this vulnerability poses a high risk by allowing unauthorized installation, manipulation, or deletion of device configurations and causing memory corruption that results in denial of service.

Technical Details of CVE-2021-1619

The following section outlines the vulnerability description, affected systems, versions, and exploitation mechanism.

Vulnerability Description

The issue stems from an uninitialized variable in the AAA function of Cisco IOS XE Software, enabling attackers to send malicious requests via NETCONF or RESTCONF to execute unauthorized actions or generate DoS conditions.

Affected Systems and Versions

The vulnerability affects Cisco IOS XE Software. Specific version details are not provided.

Exploitation Mechanism

Attackers exploit the uninitialized variable by sending a series of NETCONF or RESTCONF requests to compromise device configurations or induce memory corruption, leading to a DoS condition.

Mitigation and Prevention

Discover the immediate steps, security practices, and patching recommendations to mitigate the risks associated with CVE-2021-1619.

Immediate Steps to Take

Network administrators should apply relevant security patches, monitor suspicious network activity, and restrict access to critical systems to mitigate the risk of exploitation.

Long-Term Security Practices

Implement strong network segmentation, regularly update software and security configurations, conduct proactive security assessments, and educate users on safe network practices to enhance long-term security.

Patching and Updates

Frequently check for security advisories from Cisco and promptly apply recommended patches to address known vulnerabilities and enhance the overall security posture of Cisco IOS XE Software.