CVE-2019-1705 : What You Need to Know

Cisco Adaptive Security Appliance Software VPN Denial of Service Vulnerability

Understanding CVE-2019-1705

This CVE involves a vulnerability in the remote access VPN session manager of Cisco Adaptive Security Appliance (ASA) Software, potentially leading to a denial of service (DoS) attack on the remote access VPN services.

What is CVE-2019-1705?

An unauthenticated, remote attacker could exploit a flaw in the remote access VPN session manager, causing a DoS condition by requesting an excessive number of VPN sessions.

The Impact of CVE-2019-1705

Attack Complexity: Low
Attack Vector: Network
Base Score: 5.3 (Medium)
Availability Impact: Low
No impact on Confidentiality or Integrity
No privileges required

Technical Details of CVE-2019-1705

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability allows attackers to exploit the remote access VPN session manager, leading to a DoS condition on the VPN services.

Affected Systems and Versions

Cisco Adaptive Security Appliance (ASA) Software versions less than 9.4.4.34, 9.6.4.25, 9.8.4, 9.9.2.50, and 9.10.1.17 are affected.

Exploitation Mechanism

Attackers can exploit the flaw by requesting an excessively high number of remote access VPN sessions, triggering the DoS condition.

Mitigation and Prevention

Learn how to mitigate and prevent the CVE-2019-1705 vulnerability.

Immediate Steps to Take

Administrators can use the 'vpn-sessiondb logoff all' command on the affected device to clear the condition temporarily.
Rebooting the device is also a workaround.

Long-Term Security Practices

Regularly monitor and limit the number of remote access VPN sessions to prevent abuse.
Keep ASA Software up to date with the latest security patches.
Implement network segmentation to minimize the impact of potential DoS attacks.

Patching and Updates

Stay informed about security advisories and updates from Cisco to patch the vulnerability.