Smart Redaction & PII Protection: How Client-Side Wasm Sanitizes Legal and Financial Documents
The Illusion of Visual Redaction
A frequent security mistake made by businesses, law firms, and government contractors is placing black rectangles over sensitive text in a PDF document and saving the file.
In standard PDF structure, drawing a black box merely adds a visual polygon on top of the text layer. The underlying vector characters, metadata, and OCR layers remain completely accessible to anyone who copies the text or inspects the document stream. This has led to high-profile data leaks involving military secrets, financial figures, and personal identification data.
True Cryptographic Redaction in Heysamay Karya
True document sanitization requires surgical excision of text nodes at the byte level:
- Object Stream Decompilation: Heysamay Karya parses PDF content streams in browser memory, locating exact glyph coordinates matching targeted keywords (such as Aadhaar, PAN numbers, credit cards, or addresses).
- Byte-Level Purging: The characters and glyph streams are permanently expunged from the document dictionary and replaced with blank space prior to rasterizing the black overlay.
- Metadata Sanitization: Document title, creator tags, modification dates, and embedded thumbnails are scrubbed to eliminate forensic data trails.
Because this occurs entirely inside your local browser sandbox via WebAssembly, your sensitive records never touch third-party servers.