CVE-2018-0254 : Exploit Details and Defense Strategies

A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass configured file action policies if an Intelligent Application Bypass (IAB) with a drop percentage threshold is also configured. The vulnerability is due to incorrect counting of the percentage of dropped traffic. An attacker could exploit this vulnerability by sending network traffic to a targeted device. An exploit could allow the attacker to bypass configured file action policies, and traffic that should be dropped could be allowed into the network. Cisco Bug IDs: CSCvf86435.

Understanding CVE-2018-0254

This CVE involves a flaw in the detection mechanism of Cisco Firepower System Software that could be exploited by a remote attacker without authentication.

What is CVE-2018-0254?

The vulnerability in Cisco Firepower System Software allows attackers to bypass file action policies by manipulating the drop percentage threshold, potentially enabling harmful traffic to enter the network.

The Impact of CVE-2018-0254

Remote attackers can circumvent file action policies configured in the system, leading to potential security breaches.
Exploiting this vulnerability could allow harmful traffic to bypass security measures and enter the network.

Technical Details of CVE-2018-0254

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The flaw in Cisco Firepower System Software allows attackers to bypass configured file action policies by exploiting the incorrect calculation of dropped traffic percentages.

Affected Systems and Versions

Product: Cisco Firepower System Software
Version: Cisco Firepower System Software

Exploitation Mechanism

Attackers need to send specific network traffic to the targeted device to exploit the vulnerability.
Successful exploitation enables attackers to bypass file action policies, potentially allowing harmful traffic into the network.

Mitigation and Prevention

Protecting systems from CVE-2018-0254 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply patches and updates provided by Cisco to address the vulnerability.
Monitor network traffic for any suspicious activity that could indicate exploitation attempts.

Long-Term Security Practices

Regularly update and patch software to prevent known vulnerabilities from being exploited.
Implement network segmentation and access controls to limit the impact of potential security breaches.

Patching and Updates

Stay informed about security advisories from Cisco and apply relevant patches promptly to secure the system.