Gnuboard 5 Reflected Cross-Site Scripting Scanner

Gnuboard 5 is a popular content management system frequently utilized by webmasters and developers to create and manage dynamic websites. It is widely used in online communities, forums, and e-commerce platforms due to its customizable features and user-friendly interface. Many small to medium-sized businesses and developers rely on Gnuboard 5 for its flexibility and active support community. It is particularly popular in Korea and has a growing user base globally. The software is known for its robust plugins and themes that extend its core functionality. As with many CMS platforms, maintaining security is crucial given its deployment across diverse environments.

A Cross-Site Scripting (XSS) vulnerability allows attackers to inject malicious scripts into web pages viewed by others. In this case, the vulnerability exists because Gnuboard 5 improperly sanitizes inputs in the LGD_OID parameter. When executed, these scripts can hijack user sessions, deface websites, or redirect users to malicious sites. Cross-Site Scripting is particularly dangerous in web applications since it may lead to unauthorized access or manipulation of application data. The impact of such vulnerabilities can range from nuisance to significant security breaches, depending on the web application context. Therefore, identifying and mitigating XSS is critical in ensuring web application security.

The technical specifics of this vulnerability involve a lack of proper input filtering in the file mispwapurl.php for the parameter LGD_OID. When an attacker provides a crafted payload, such as a JavaScript script, it is reflected back to users accessing the vulnerable endpoint. This lack of sanitization means any user navigating to a compromised URL may unknowingly execute the attacker’s code. Specifically, this endpoint returns a status code of 200 along with a content type of text/html, allowing the script to execute successfully in the victim's browser. The vulnerability reflects the input directly back to the page, executing it within the user's session context.

When exploited, such vulnerabilities can have serious consequences, including data theft, user impersonation, session hijacking, and malware deployment. The most immediate risks involve loss of user trust and potential legal implications from data breaches. Attackers may also use this vulnerability to conduct phishing attacks or create persistent malware threats. Longer-term impacts could involve reputational damage to brands using Gnuboard 5, leading to customer attrition and loss of revenue. Such incidents highlight the importance of securing web applications through proper input validation and output encoding.

REFERENCES

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• https://vulners.com/huntr/25775287-88CD-4F00-B978-692D627DFF04