Technical trust center

Security claims you can inspect.

This page separates file-content privacy from metadata, explains the actual recovery path, names the infrastructure providers, and states the limits of browser encryption.

Technical claims reviewed 16 July 2026

01 / Data flow

Plaintext stays at the endpoints.

VaultDrop transports and stores the encrypted form. The sender and recipient devices handle plaintext.

01

Sender browser

Creates an AES-256-GCM file key and encrypts file contents before upload.

02

VaultDrop service

Authorises the request, manages multipart state, and issues time-limited object requests.

03

R2 EU jurisdiction

Stores encrypted file objects. Jurisdictional restriction applies to the object bucket.

04

Recipient browser

Downloads encrypted bytes and opens the content locally with authorised key material.

Infrastructure reference: Cloudflare R2 jurisdictional restrictions

02 / Visibility

Encryption does not hide every fact.

The table below is the practical boundary. It avoids treating file-content encryption as total anonymity.

Data VaultDrop access Why
File contents No plaintext access Encrypted in the sender's browser before upload.
Decryption material Wrapped key or URL fragment Account file keys are wrapped. Anonymous transfer keys stay in the link fragment, which browsers do not send in HTTP requests.
File metadata Visible to the service Names, sizes, folder paths, and timestamps are used to operate the workspace and delivery flow.
Account identity Visible to the service Email, name, authentication state, subscription, and security events are processed for account operation.
Network metadata Visible in limited logs IP address, browser type, and access timestamps support security, abuse prevention, and audit trails.
Share password Hashed Password-protected share passwords are stored as a one-way bcrypt hash, not as plaintext.

Read the full privacy and retention policy

03 / Recovery

Resume from confirmed parts, not from zero.

Registered files at or above 100 MiB use multipart upload. Recovery state remains in the browser for up to seven days.

RECOVERY TEST / 2026-07-16 PASS
  1. 01session statusparts 1, 3 confirmed
  2. 02local matchname, size, modified time
  3. 03wrapped keyrestored after unlock
  4. 04upload queueparts 2, 4 only
  5. 05completeone encrypted object

What is verified

  • Wrapped encryption material can be restored only after the account key is unlocked.
  • A changed name, size, or modification time blocks automatic matching.
  • Server-confirmed chunks are excluded from the new upload queue.
  • Expired object URLs are replaced before remaining parts continue.

This is a code-path test, not a claim that every browser, network, or 1 TB file has been certified. The public runbook lets a buyer repeat the interruption test with a real file.

Open the recovery proof and test runbook

Storage primitive reference: Cloudflare multipart upload behavior

04 / Providers

Named services, narrow roles.

No “zero subprocessors” promise. These providers perform specific operational functions.

01

Cloudflare

Application execution, network delivery, security, D1 metadata, transactional account email, and R2 object storage

Encrypted file objects use an R2 bucket configured with the EU jurisdiction.
02

Stripe

Paid plan checkout, subscription management, invoices, and payment records

Stripe receives billing data, not file contents.
03

Google

Optional sign-in

Used only when a user chooses Google sign-in. VaultDrop does not request Drive, Gmail, or other Google content.

05 / Limits

What browser encryption cannot protect.

A useful security page includes the boundary conditions.

01

A compromised endpoint

Malware, an unsafe browser extension, or a person with device access can see plaintext while the file is open.

02

A leaked share link

Anyone who receives a complete non-password share link may possess the key fragment. Verify recipients and use a separate channel for sensitive access details.

03

Visible metadata

Names, sizes, account information, and operational logs remain service data even when file contents are encrypted.

04

Application code trust

The browser runs code delivered by VaultDrop. This page does not claim an independent cryptographic audit or protection from malicious code served to the browser.

Test the workflow

Start small, interrupt it, recover it.

Create a free workspace, use a representative file over 100 MiB, and follow the public recovery runbook before moving a real client delivery.

Create a free workspace Read the test runbook