CVE-2019-1957 : Vulnerability Insights and Analysis

Cisco IoT Field Network Director TLS Renegotiation Denial of Service Vulnerability

Understanding CVE-2019-1957

This CVE involves a weakness in the Cisco IoT Field Network Director's web interface that could be exploited by an unauthorized attacker, potentially leading to a denial of service (DoS) by causing excessive CPU usage on the affected device.

What is CVE-2019-1957?

The vulnerability stems from the incorrect handling of Transport Layer Security (TLS) renegotiation requests within the Cisco IoT Field Network Director's web interface. An attacker could exploit this by sending a high volume of renegotiation requests, escalating system resource consumption and resulting in a DoS condition.

The Impact of CVE-2019-1957

The vulnerability has a CVSS base score of 5.3, indicating a medium severity issue. If successfully exploited, it could lead to excessive CPU usage, rendering the affected device unavailable due to a denial of service attack.

Technical Details of CVE-2019-1957

Vulnerability Description

The vulnerability in the Cisco IoT Field Network Director allows an unauthorized attacker to trigger high CPU usage, leading to a denial of service condition. It is caused by improper handling of TLS renegotiation requests.

Affected Systems and Versions

Product: Cisco IoT Field Network Director (IoT-FND)
Vendor: Cisco
Version: Unspecified

Exploitation Mechanism

Attack Complexity: Low
Attack Vector: Network
Privileges Required: None
User Interaction: None
Scope: Unchanged
Vector String: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Mitigation and Prevention

Immediate Steps to Take

Apply the latest security patches 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 all software and firmware to prevent known vulnerabilities.
Implement network segmentation and access controls to limit the impact of potential attacks.

Patching and Updates

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