Vulnerability Scanners
Relevant source files
The following files were used as context for generating this wiki page:
- nettacker/modules/vuln/wp_plugin_cve_2021_38314.yaml
- nettacker/modules/vuln/nextjs_cve_2025_55182.yaml
- nettacker/modules/vuln/vite_cve_2025_31125.yaml
- nettacker/modules/vuln/apache_cve_2021_42013.yaml
- nettacker/modules/vuln/apache_cve_2021_41773.yaml
- nettacker/modules/vuln/paloalto_panos_cve_2025_0108.yaml
- nettacker/modules/vuln/http_cors.yaml
- README.md
Vulnerability Scanners in OWASP Nettacker are modular components designed to automate the detection of security flaws, misconfigurations, and specific CVEs across various network targets. These scanners leverage a YAML-based definition format to execute multi-step network probes, primarily using the HTTP protocol to identify vulnerabilities ranging from path traversal and information leakage to remote code execution (RCE).
The framework provides a unified engine to execute these modules against single IPs, ranges, or domains, allowing for large-scale security audits. Each scanner defines specific payloads, request methods, and expected response conditions (regex or status codes) to determine the vulnerability status of a target.
Sources: README.md:16-25, nettacker/modules/vuln/nextjs_cve_2025_55182.yaml:1-25
Module Architecture and Definition
Vulnerability scanners are defined as YAML files located within the nettacker/modules/vuln/ directory. Each module contains metadata for identification and a set of instructions for the execution engine.
Module Information (info block)
The info block provides essential metadata used for categorization and reporting:
- Name & Author: Unique identifier for the module and the contributor.
- Severity: Numerical or descriptive ranking of the vulnerability (e.g., 7.5, 9, 10.0).
- Profiles: Tags used to group modules (e.g.,
vuln,http,cve,critical_severity). - Description & Reference: Technical details and external links (NVD/CVE entries).
Sources: nettacker/modules/vuln/apache_cve_2021_42013.yaml:1-12, nettacker/modules/vuln/vite_cve_2025_31125.yaml:1-17
Payload and Step Logic
The payloads block defines the actual execution logic, supporting multiple libraries (primarily http). Each payload consists of one or more steps that the engine executes sequentially.
The diagram above shows the general execution flow of a vulnerability scanner step.
Sources: nettacker/modules/vuln/wp_plugin_cve_2021_38314.yaml:14-30, nettacker/modules/vuln/http_cors.yaml:11-44
Execution Engine Components
Vulnerability scanners rely on several core engine features to perform effective probes:
1. Nettacker Fuzzer
The nettacker_fuzzer sub-block within a URL definition allows for dynamic input generation. It typically includes:
- Input Format: A template string using placeholders like
{{schema}},{target}, and{{ports}}. - Data Iteration: Lists of schemas (http, https), ports (80, 443, 8443), and paths to be tested.
- Interceptors: Optional functions to modify data on the fly (e.g.,
generate_and_replace_md5).
Sources: nettacker/modules/vuln/paloalto_panos_cve_2025_0108.yaml:30-45, nettacker/modules/vuln/wp_plugin_cve_2021_38314.yaml:26-40
2. Response Validation
The engine evaluates the success of a scan based on response conditions. These conditions use logic operators (and, or) to check multiple attributes:
| Attribute | Description | Example Usage |
|---|---|---|
status_code | HTTP response code check | regex: "200" |
headers | Specific header presence or value | Content-Type: regex: text/html |
content | Response body pattern matching | regex: "root:(\\S+):" |
Sources: nettacker/modules/vuln/apache_cve_2021_41773.yaml:45-53, nettacker/modules/vuln/vite_cve_2025_31125.yaml:44-55
Common Vulnerability Patterns
The following table summarizes common vulnerability types handled by existing scanners:
| Vulnerability Type | Implementation Strategy | Key Module Example |
|---|---|---|
| Path Traversal / LFI | Attempts to access /etc/passwd or win.ini via encoded paths. | apache_cve_2021_42013 |
| Auth Bypass | Uses path confusion (e.g., %252e%252e/) to reach internal admin scripts. | paloalto_panos_cve_2025_0108 |
| Information Leak | Queries specific endpoints and looks for sensitive MD5 hashes or signatures. | wp_plugin_cve_2021_38314 |
| Remote Code Execution | Sends complex multipart/form-data payloads to trigger flight protocol exploits. | nextjs_cve_2025_55182 |
| CORS Misconfig | Fuzzes Origin headers to detect reflected or wildcard allow-list policies. | http_cors |
Sources: nettacker/modules/vuln/apache_cve_2021_41773.yaml:23-44, nettacker/modules/vuln/nextjs_cve_2025_55182.yaml:35-50, nettacker/modules/vuln/http_cors.yaml:1-10
Multi-Step Interaction
Complex scanners utilize sequential steps where the outcome of one step informs the status or where multiple payloads are required for different operating systems.
The sequence above illustrates the multi-platform approach used in critical RCE scanners.
Sources: nettacker/modules/vuln/nextjs_cve_2025_55182.yaml:30-80
Conclusion
Vulnerability Scanners in OWASP Nettacker represent a highly flexible, YAML-driven system for network security assessment. By separating the vulnerability logic (YAML) from the execution engine (Python), the project allows for rapid updates to include new CVEs and detection techniques without altering core code. The framework's ability to handle complex fuzzed inputs and multi-step validation logic makes it suitable for detecting a wide range of web and network-level security flaws.