PrivacyScrubber

PrivacyScrubber
Original author	Ilya Sibiryakov
Developer	Brand Me Web
Operating system	Cross-platform (Browser extension, CLI)
Type	Data loss prevention software, Computer security
Website	privacyscrubber.com

PrivacyScrubber is a client-side data sanitization tool and security gateway designed to redact Personally Identifiable Information (PII) and Protected Health Information (PHI) before transmission to cloud-based Large Language Models (LLMs). It employs a Zero-Trust Data Sanitization (ZTDS) architecture, which aims to process sensitive data within the local computing environment.

Architecture and Technology

PrivacyScrubber operates entirely offline. The core tokenization engine intercepts sensitive entities (such as names, Social Security numbers, and credit card PANs) and replaces them with synthetic tokens (e.g., [NAME_1]).

The state mapping linking the original data to the tokens is encrypted in the browser's volatile memory using the XChaCha20-Poly1305 authenticated encryption algorithm, with keys derived via Argon2id. Temporary extraction buffers are overwritten at the byte level prior to memory garbage collection.

Integration

PrivacyScrubber functions across multiple environments:

• Web Application & Browser Extension: Integrates into the Document Object Model (DOM) to sanitize text inputs for web-based AI interfaces.
• Model Context Protocol (MCP): Functions as a local MCP server, creating a local context window for autonomous AI developer tools to manage the exposure of environment variables and source code.

Compliance Framework

The tool is designed to address several regulatory frameworks by shifting the sanitization workload to the endpoint:

• HIPAA & HITECH: Redacting PHI identifiers.
• FERPA: Masking student identities.
• PCI-DSS & GLBA: Securing consumer financial records.
• GDPR & CPRA: Supporting data minimization and the Right to be forgotten.