CVE-2023-44390 : What You Need to Know

HTMLSanitizer library is vulnerable to Cross-site Scripting (XSS) attacks when processing foreign content, exposing affected systems to potential security risks.

Understanding CVE-2023-44390

HTMLSanitizer, a .NET library, is susceptible to XSS attacks in scenarios where foreign content is permitted, such as allowing

svg

or

math

elements. This vulnerability enables threat actors to inject malicious HTML, including JavaScript code, by bypassing input sanitization.

What is CVE-2023-44390?

CVE-2023-44390 highlights a security flaw in HTMLSanitizer library that allows attackers to execute XSS attacks by exploiting configurations that permit foreign content, leading to arbitrary code injection.

The Impact of CVE-2023-44390

The vulnerability in HTMLSanitizer library poses a medium severity risk, enabling attackers to execute XSS attacks by injecting malicious content via permitted elements, potentially compromising the integrity and confidentiality of affected systems.

Technical Details of CVE-2023-44390

The HTMLSanitizer vulnerability in version < 8.0.723 and >= 8.1.0-beta, < 8.1.722-beta permits XSS attacks when foreign content is processed. The exploit requires user interaction and affects systems with network accessibility.

Vulnerability Description

The flaw in HTMLSanitizer library allows threat actors to execute XSS attacks by injecting malicious content via permitted elements, affecting systems configured to allow foreign content.

Affected Systems and Versions

Systems using HTMLSanitizer versions < 8.0.723 and >= 8.1.0-beta, < 8.1.722-beta are vulnerable to XSS attacks when processing foreign content, potentially compromising system integrity.

Exploitation Mechanism

Attackers exploit the HTMLSanitizer vulnerability by injecting malicious HTML, including JavaScript code, via permitted elements like

svg

or

math

, bypassing input sanitization and compromising system security.

Mitigation and Prevention

To address CVE-2023-44390, immediate action is crucial to mitigate the risk of XSS attacks and protect systems from potential exploitation.

Immediate Steps to Take

Upgrade HTMLSanitizer library to versions 8.0.723 or >= 8.1.722-beta to prevent XSS attacks on systems processing foreign content. Ensure proper sanitization of user input and restrict access to potentially vulnerable elements.

Long-Term Security Practices

Implement robust input validation mechanisms to detect and prevent XSS vulnerabilities in web applications, emphasizing secure coding practices and ongoing security assessments.

Patching and Updates

Regularly monitor for security patches and updates from HTMLSanitizer to address known vulnerabilities, ensuring that systems remain protected against emerging threats.