Cryptographic Operations & Primitives

Zero-Trust Cryptographic Blueprint

PrivacyScrubber secures sensitive data not by policy, but by mathematics. Our Zero-Trust Data Sanitization (ZTDS) model operates entirely in browser memory, utilizing military-grade cryptography to mask and rehydrate personal data without external servers.

The Client-Side Cryptographic Pipeline

1

Local Detection & Tokenization

Sensitive PII elements are scanned using our local JS regex matching engine. Raw strings are replaced with safe, context-preserving semantic tags (e.g., [NAME_1], [EMAIL_2]).

2

In-Memory Key-Value SessionMap

The original data mapping is stored in the browser's volatile RAM (the sessionMap). It is strictly isolated per browser tab using active tabId prefixes, preventing cross-tab leakage.

3

Teams Session Cryptography (Argon2id + XChaCha20-Poly1305)

For Team Session Handoffs, we compile libsodium-wrappers-sumo to WebAssembly. Decryption keys are derived locally using Argon2id. Payloads are encrypted using XChaCha20-Poly1305 before sharing. Our servers only see encrypted blobs—they never hold the decryption keys.

Cryptographic Standards & Primitives

PrivacyScrubber does not invent proprietary cryptography. We exclusively implement industry-standard algorithms compiled to WebAssembly via Libsodium to prevent timing attacks and side-channel leakage.

Key Derivation: Argon2id

We derive 256-bit symmetric keys from local Team Magic Link parameters using Argon2id. This prevents brute-force key retrieval from intercepted links and ensures keys are generated dynamically inside the client DOM.

Authenticated Encryption: XChaCha20-Poly1305

Encrypted session blobs are constructed using XChaCha20-Poly1305 (AEAD). This ensures confidentiality and cryptographic integrity—if an encrypted session is modified or tampered with in-transit, decryption fails instantly.

Two-Tier Fleet Governance Architecture

PrivacyScrubber delivers unified corporate AI governance without restricting individual speed. Our architecture separates global compliance controls from worker-level adaptability:

Central CISO Hard Lock

Security leads configure company-wide regex rules and select industry profiles in the Team Hub. Activating the Hard Lock makes the base policy read-only and locks the extension protection toggle permanently ON across managed endpoints.

Instant Zero-Proxy Rollout

Blueprints are distributed instantly via 1-click encrypted URLs, config files, or Google Workspace/Microsoft Intune MDM policies. There are zero proxy servers to configure, zero network hops, and zero latency overhead.

Local Worker Flexibility (Additive Overlay)

Employees can add temporary [LOCAL] rules for active client codenames directly from the extension popover without filing IT tickets. These local rules overlay on top of the locked corporate baseline additively without degrading compliance.

Zero Storage & Memory Lifecycle

PrivacyScrubber enforces a strict zero-data-at-rest architecture. Understanding our memory lifecycle is crucial for compliance officers and AppSec teams:

  • No Local Disk Storage: We do not write raw PII to localStorage, cookies, IndexedDB, or the client file system. All original PII mappings exist solely as temporary variables in the JS garbage-collector scope.
  • Tab Isolation Shield: To prevent session leakage across browser tabs, all memory maps are scoped using the active tabId provided by the extension service worker. Tab A cannot access the PII mapping of Tab B.
  • Volatile Termination: The moment you close the active browser tab or refresh the page, the volatile RAM is flushed. The keys mapping the tokens back to PII are permanently destroyed.

How to Verify Our Zero-Server Claim

We do not ask you to trust our promises. We invite you to perform a local network audit using standard Google Chrome Developer Tools.

  1. Open the PrivacyScrubber utility on your browser.
  2. Press F12 or right-click the page and select Inspect to open Developer Tools.
  3. Select the Network tab and select the "Fetch/XHR" filter.
  4. Type sensitive names or credit card numbers into the input field and click Protect Now.
  5. Observe the Network console. You will see zero outbound requests containing your raw text or token mappings. The only network calls permitted are the asynchronous team subscription verification checks (excluding any prompt data).

Airplane Mode Verification: Disconnect your Wi-Fi or unplug your ethernet cable. PrivacyScrubber remains 100% functional, proving that all tokenization and text reconstruction run natively on your local hardware.

Regulatory Compliance Mapping

StandardRequirementPrivacyScrubber Cryptographic Alignment
GDPR Article 32Pseudonymization and encryption of personal data to ensure ongoing confidentiality.PII is replaced with generic semantic tokens locally in the browser DOM before hitting cloud API endpoints, preventing exposure to LLM training logs.
SOC 2 CC9.1Maintains confidentiality of system data in transit and at rest.Uses in-memory RAM-only SessionMap to store de-identification keys. Original mappings are destroyed upon closing the active browser tab.
NIST AI RMFManage security risks of third-party AI integrations.Intercepts prompts and sanitizes files (.txt, .docx, .pdf) natively on the endpoint, eliminating the risk of data leakage to external models.