CVE-2023-20247 : Vulnerability Insights and Analysis

This CVE-2023-20247 relates to a vulnerability found in the remote access SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software. The vulnerability could allow an authenticated, remote attacker to bypass a configured multiple certificate authentication policy and connect using only a valid username and password.

Understanding CVE-2023-20247

This section will delve into the details of CVE-2023-20247, including the vulnerability description, impact, affected systems, exploitation mechanism, mitigation, and prevention strategies.

What is CVE-2023-20247?

The vulnerability in CVE-2023-20247 is a result of improper error handling during remote access VPN authentication. Attackers could exploit this vulnerability by sending crafted requests during remote access VPN session establishment, ultimately allowing them to bypass the configured multiple certificate authentication policy while retaining the privileges and permissions associated with the original connection profile.

The Impact of CVE-2023-20247

The impact of this vulnerability is rated as medium with a CVSS base score of 5.0. It could potentially allow an authenticated attacker to circumvent authentication policies and gain unauthorized access using only a valid username and password.

Technical Details of CVE-2023-20247

In this section, we will discuss the vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability in the remote access SSL VPN feature of Cisco ASA and FTD Software allows attackers to bypass multiple certificate authentication policies during the authentication process.

Affected Systems and Versions

The vulnerability affects various versions of Cisco ASA Software and Cisco FTD Software. Specifically, multiple versions ranging from 9.8.1 to 9.19.1 for ASA Software and versions 6.2.3 to 7.3.1 for FTD Software are identified as affected.

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specifically crafted requests during the establishment of a remote access VPN session.

Mitigation and Prevention

In this section, we will explore the immediate steps to take, long-term security practices, and the importance of patching and updates.

Immediate Steps to Take

To mitigate the risk associated with CVE-2023-20247, organizations should enforce strong, unique passwords for user accounts, monitor network traffic for any suspicious activities, and restrict access to the VPN to only authorized personnel.

Long-Term Security Practices

Implementing multi-factor authentication, conducting regular security audits, keeping systems up-to-date with the latest patches, and providing cybersecurity awareness training to employees are essential long-term security practices to enhance overall defense against potential threats.

Patching and Updates

Cisco has released patches to address the vulnerability in affected software versions. Organizations are strongly advised to apply these patches promptly to mitigate the risk of exploitation and ensure the security of their systems.