Generic NoSQL Injection Vulnerability Scanner

NoSQL databases such as MongoDB, CouchDB, Redis and Elasticsearch are widely used by modern web applications for flexible schema design and horizontal scalability. They are commonly deployed by developers for storing JSON-like documents, session data, search indexes, and caching. These systems are used across startups and enterprises in web apps, microservices, mobile backends, and analytics pipelines. Administrators and developers rely on application-layer code to translate user input into database queries or commands. When query construction is performed insecurely in application code, user input can alter query structure. This scanner targets typical web application stacks that pass user-controlled data into NoSQL queries without proper validation or safe APIs.

NoSQL Injection occurs when user-controlled input is embedded into NoSQL queries or commands in a way that allows attackers to change the intended logic of the query. Unlike SQL injection, NoSQL injection often leverages JSON operators, query objects, or special token formats to influence query behavior. Exploits may enable attackers to bypass authentication, enumerate or exfiltrate data, modify or delete records, or execute database commands. Common risky patterns include directly merging JSON payloads into queries, using eval-like functions, or accepting structured parameters without strict typing. The vulnerability surface is present both in REST/HTTP endpoints and in backend services that accept untrusted payloads. Detection requires sending crafted payloads that reveal whether injected operators or control structures are interpreted by the database.

Technically, the vulnerability appears when application code constructs NoSQL queries by concatenating or deserializing user input into query objects (for example, building a MongoDB query from a JSON body). Vulnerable endpoints include login/auth endpoints (e.g., where an object like { "username": user, "password": pass } can be manipulated), search or filter APIs that accept JSON criteria, and any endpoint that forwards user JSON directly to database drivers. Attack payloads often use operator forms such as {"$ne": ""}, {"$gt": 0}, or injected JSON structures that change query semantics. In some systems, boolean injection (e.g., sending {"$or":[{}, { "role": "admin" } ]}) or use of MongoDB $where with JavaScript can lead to remote code execution. The scanner probes parameters, request bodies, and headers with a set of crafted payloads and checks responses and behavior changes to determine exploitable injection points.

If successfully exploited, NoSQL Injection can allow attackers to bypass authentication checks, read or modify sensitive records, delete data, or elevate privileges within the application. Attackers may exfiltrate user data, credentials, API keys, or internal configuration stored in the database. In advanced cases where the database supports server-side scripting, injection can lead to remote code execution or lateral movement. The integrity and availability of the application can be compromised through unauthorized writes or destructive commands. Business impact ranges from privacy breaches and regulatory exposure to full application takeover depending on the environment and privileges of the database account.

REFERENCES

• https://owasp.org/www-community/attacks/NoSQL_Injection
• https://portswigger.net/web-security/nosql-injection