CVE-2023-38320 : What You Need to Know

This article provides details about CVE-2023-38320, a vulnerability discovered in OpenNDS Captive Portal.

Understanding CVE-2023-38320

CVE-2023-38320 is a vulnerability found in OpenNDS Captive Portal before version 10.1.2, leading to a Denial-of-Service condition.

What is CVE-2023-38320?

An issue was discovered in OpenNDS Captive Portal before version 10.1.2. It has a show_preauthpage NULL pointer dereference that can be triggered with a crafted GET HTTP request with a missing User-Agent header.

The Impact of CVE-2023-38320

Exploiting this vulnerability results in crashing OpenNDS, causing a Denial-of-Service condition for users.

Technical Details of CVE-2023-38320

The technical details of CVE-2023-38320 include:

Vulnerability Description

The vulnerability involves a NULL pointer dereference in OpenNDS Captive Portal when a specific crafted GET HTTP request is sent without a User-Agent header.

Affected Systems and Versions

All versions of OpenNDS Captive Portal before 10.1.2 are affected by this vulnerability.

Exploitation Mechanism

By sending a crafted GET HTTP request with a missing User-Agent header, attackers can trigger a NULL pointer dereference and crash OpenNDS, leading to a Denial-of-Service situation.

Mitigation and Prevention

To mitigate and prevent exploitation of CVE-2023-38320, consider the following steps:

Immediate Steps to Take

Upgrade OpenNDS Captive Portal to version 10.1.2 or later.
Implement strict input validation mechanisms to handle HTTP requests.
Monitor network traffic for any suspicious activity.

Long-Term Security Practices

Regularly update and patch OpenNDS to the latest version.
Conduct security audits and assessments to identify and address vulnerabilities.

Patching and Updates

Refer to the official OpenNDS Captive Portal release page here for patches and updates.