CVE-2020-20253 : Security Advisory and Response

Mikrotik RouterOs before 6.47 (stable tree) is vulnerable to a division by zero flaw in the /nova/bin/lcdstat process, allowing an authenticated remote attacker to trigger a Denial of Service (DoS) attack.

Understanding CVE-2020-20253

This CVE identifies a specific vulnerability in Mikrotik RouterOs that can be exploited by an authenticated remote attacker to cause a DoS by exploiting a divide by zero error.

What is CVE-2020-20253?

The CVE-2020-20253 vulnerability is a division by zero issue in the /nova/bin/lcdstat process of Mikrotik RouterOs versions prior to 6.47. This flaw can be abused by a remote attacker with authentication to disrupt services by triggering a divide by zero error.

The Impact of CVE-2020-20253

The exploitation of this vulnerability can lead to a Denial of Service condition, causing disruption to the affected Mikrotik RouterOs system and potentially impacting network availability and performance.

Technical Details of CVE-2020-20253

This section provides more in-depth technical insights into the CVE-2020-20253 vulnerability.

Vulnerability Description

The vulnerability in Mikrotik RouterOs before version 6.47 involves a division by zero flaw in the /nova/bin/lcdstat process, which can be leveraged by an authenticated remote attacker to execute a DoS attack.

Affected Systems and Versions

Product: Mikrotik RouterOs
Vendor: Mikrotik
Versions affected: All versions before 6.47

Exploitation Mechanism

The vulnerability can be exploited by an authenticated remote attacker to send specially crafted requests to the /nova/bin/lcdstat process, triggering a divide by zero error and causing a DoS condition.

Mitigation and Prevention

Protecting systems from CVE-2020-20253 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update Mikrotik RouterOs to version 6.47 or later to mitigate the vulnerability.
Monitor network traffic for any suspicious activity targeting the /nova/bin/lcdstat process.

Long-Term Security Practices

Implement strong authentication mechanisms to prevent unauthorized access to the system.
Regularly apply security patches and updates to ensure system resilience against known vulnerabilities.
Conduct security audits and assessments to identify and address potential weaknesses in the network infrastructure.
Educate users and administrators about security best practices to enhance overall cybersecurity posture.

Patching and Updates

Ensure timely installation of security patches released by Mikrotik to address the division by zero vulnerability in the /nova/bin/lcdstat process.