File Upload Bypass Scanner
Tests file upload restrictions for extension and content-type bypasses.
What is File Upload Bypass?
File upload bypass testing attempts to circumvent upload restrictions to upload malicious files. Techniques include extension manipulation (.php.jpg), content-type spoofing, null bytes, case variation, double extensions, and exploiting parser differences between validation and execution.
Why is This Important?
Bypassing upload restrictions to upload web shells provides immediate remote code execution. This is one of the most reliable paths to complete server compromise, allowing attackers to access all data and pivot to other systems.
How It Works
1. Web Crawling
Intelligent crawling discovers all endpoints, forms, parameters, and dynamic content across your web application.
2. Payload Injection
AI-powered payloads test each input vector for web vulnerabilities with context-aware attack patterns.
3. Response Analysis
Advanced analysis detects vulnerability signatures in responses, confirming exploitability with proof-of-concept.
Key Capabilities
Industry-leading web security testing powered by AI, trusted by security teams worldwide for accurate vulnerability detection.
- Deep web crawling with JavaScript rendering support
- Context-aware payload generation for each parameter
- False positive elimination through response analysis
- OWASP Top 10 and CWE compliance mapping
- Seamless CI/CD and DevSecOps integration
Frequently Asked Questions
What bypass techniques are most effective?
Double extensions (.php.jpg), alternative extensions (.phtml, .php5), null bytes (.php%00.jpg), content-type manipulation, and exploiting differences between validators and web servers.
Is checking file content enough?
Better than extension checks alone, but sophisticated payloads can have valid magic bytes while still being executable. Defense in depth is essential.
Where should uploaded files be stored?
Outside the web root, in a separate domain/CDN for serving, with randomized filenames. Never store in a location where web server will execute them.
Can image files contain code?
Yes, polyglot files can be valid images that also contain executable code. PHP can be embedded in image metadata, EXIF data, or after image content.
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