CVE-2017-3807 : Vulnerability Insights and Analysis

A vulnerability in the Common Internet Filesystem (CIFS) code in the Clientless SSL VPN feature of Cisco ASA Software, Major Releases 9.0-9.6, allows a remote attacker with authentication to trigger a heap overflow by exploiting inadequate user input validation.

Understanding CVE-2017-3807

This CVE involves a flaw in the CIFS code within the Clientless SSL VPN functionality of Cisco ASA Software.

What is CVE-2017-3807?

The vulnerability in the Clientless SSL VPN feature of Cisco ASA Software, Major Releases 9.0-9.6, enables a remote attacker with authentication to cause a heap overflow due to insufficient validation of user input. By sending a carefully crafted URL, the attacker can exploit this weakness, potentially leading to a system reload or code execution.

The Impact of CVE-2017-3807

Successful exploitation could result in a system reload or potential code execution by the remote attacker.
The vulnerability affects systems configured in routed firewall mode, in single or multiple context mode.
It is triggered by both IPv4 and IPv6 traffic and requires a valid TCP connection.
The attacker must have valid credentials to log in to the Clientless SSL VPN portal.
Affected products include Cisco ASA 5500 Series Adaptive Security Appliances, Cisco ASA 5500-X Series Next-Generation Firewalls, and more.

Technical Details of CVE-2017-3807

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability allows a remote attacker to trigger a heap overflow in the CIFS code of the Clientless SSL VPN feature of Cisco ASA Software.

Affected Systems and Versions

Cisco ASA Software with Clientless SSL VPN portal enabled Major Releases 9.0-9.6

Exploitation Mechanism

The attacker needs authentication and can exploit the vulnerability by sending a carefully crafted URL to the affected system.

Mitigation and Prevention

Protect your systems from CVE-2017-3807 with these mitigation strategies.

Immediate Steps to Take

Apply the necessary patches provided by Cisco to address the vulnerability.
Monitor network traffic for any signs of exploitation.
Restrict access to the affected systems.

Long-Term Security Practices

Regularly update and patch your Cisco ASA Software to prevent vulnerabilities.
Implement strong authentication mechanisms to prevent unauthorized access.

Patching and Updates

Stay informed about security advisories from Cisco and apply patches promptly to secure your systems.