CVE-2019-1718 : Security Advisory and Response

Cisco Identity Services Engine SSL Renegotiation Denial of Service Vulnerability

Understanding CVE-2019-1718

Cisco Identity Services Engine (ISE) version 2.1 is susceptible to a denial of service (DoS) attack due to a flaw in its web interface handling SSL renegotiation requests.

What is CVE-2019-1718?

The vulnerability in Cisco ISE allows an unauthenticated remote attacker to trigger excessive CPU usage, leading to a DoS condition by flooding the system with SSL renegotiation requests.

The Impact of CVE-2019-1718

CVSS Base Score: 5.3 (Medium Severity)
Attack Vector: Network
Attack Complexity: Low
Availability Impact: Low
Successful exploitation can result in a DoS situation due to increased resource consumption on the affected system.

Technical Details of CVE-2019-1718

Cisco ISE SSL Renegotiation DoS Vulnerability

Vulnerability Description

The flaw in Cisco ISE's web interface allows remote attackers to exploit SSL renegotiation requests, causing high CPU usage and potential denial of service.

Affected Systems and Versions

Product: Cisco Identity Services Engine Software
Vendor: Cisco
Version: 2.1(0.907)

Exploitation Mechanism

Attackers can flood the system with SSL renegotiation requests, overwhelming the system and leading to a DoS condition.

Mitigation and Prevention

Protecting against CVE-2019-1718

Immediate Steps to Take

Apply vendor-provided patches or updates promptly.
Monitor network traffic for any unusual SSL renegotiation patterns.
Implement network segmentation to limit the impact of potential attacks.

Long-Term Security Practices

Regularly update and patch all software and systems.
Conduct security assessments and penetration testing to identify vulnerabilities.
Educate users and administrators on best security practices.

Patching and Updates

Cisco has released patches to address the vulnerability.
Ensure all instances of Cisco ISE are updated to the patched versions.