Cascade File Upload Without Validation
Critical file upload vulnerability after Cascade removed file validation. Users can upload arbitrary files including executables or malicious scripts. Files are stored in web-accessible directory and can be executed on the server.
This is a critical security issue requiring immediate attention.
Error Messages You Might See
Common Causes
- Cascade removed file type validation - accepts any file extension
- Files saved directly to web root without sanitization
- Cascade removed file size limits, allowing disk exhaustion
- Filenames not sanitized - can contain path traversal sequences (../)
How to Fix It
Validate file types by checking MIME type and extension whitelist. Limit file size (e.g., 10MB). Sanitize filenames to prevent path traversal. Store files outside web root if possible. Set proper permissions so files can't be executed. Virus scan uploads if dealing with user files. Generate random filenames.
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Get HelpFrequently Asked Questions
How do I validate file uploads safely?
Check MIME type, file extension (whitelist), file size, scan for viruses. Store outside web root.
How do I prevent path traversal?
Sanitize filename: remove /, \, .., null bytes. Generate random filename instead of using user input.