OpenStreetMap Nominatim Content-Security-Policy Bypass Scanner

OpenStreetMap Nominatim is widely used by developers and organizations to offer geolocation services, such as searching and reverse geocoding, within web and mobile applications. It provides a public API for software engineers to integrate mapping functionalities into servers and applications. Due to its open nature, Nominatim is employed in numerous environments, making it essential for various location-based services across different sectors. Users rely on it for its accuracy in identifying geographical locations based on given data points. Organizations utilizing Nominatim benefit from its open-source capabilities, letting them customize features according to their needs. The continuous support and updates from a dedicated community enhance its reliability in global mapping initiatives.

The scanner identifies a Cross-Site Scripting (XSS) vulnerability within OpenStreetMap Nominatim due to improper Content-Security-Policy implementation. This vulnerability occurs when attackers can execute malicious scripts in a user's browser in the context of a trusted website, potentially leading to unauthorized actions. The XSS vulnerability can be exploited by crafting a payload that bypasses the Content-Security-Policy restrictions put in place, thereby impacting users who visit the affected service. Detecting this vulnerability is crucial in preventing data theft, session hijacking, and other malicious operations. Proper implementation of security controls can mitigate the impacts of XSS attacks, ensuring the safety of users interacting with online mapping services.

The vulnerability arises from the insufficient definition of Content-Security-Policy headers by OpenStreetMap Nominatim, allowing for potential bypasses. A malicious actor could insert a script tag into a query parameter, injecting unwanted code that the application will subsequently execute. The vulnerability check involves sending a payload to the affected endpoint to determine if the CSP configuration is bypassable, which could enable undesired script execution. The primary focus is on the "Content-Security-Policy" header and its ability to block external script execution properly. The scanner utilizes navigational actions to determine whether a bypass occurs when faced with the payload. Identifying such vulnerabilities promptly allows organizations to take corrective actions to secure their applications.

When exploited, this vulnerability could lead to the execution of arbitrary scripts within a user's web session, resulting in unauthorized access to sensitive information or user accounts. The implications of a successful attack include identity theft, financial fraud, or further network compromise through the affected user's identity. Attackers might leverage this vulnerability to disseminate propaganda or misinformation, causing reputational damage to the affected service provider. Additionally, script execution can facilitate the unauthorized delivery of malicious payloads, leading to potential infections with malware or ransomware. Therefore, the XSS vulnerability in OpenStreetMap Nominatim poses significant risks requiring immediate attention and resolution to protect users' privacy and security.

REFERENCES

• https://github.com/renniepak/CSPBypass/blob/main/data.tsv