Creator here. One goal from the beginning was to keep everything local. FileVeil never uploads your files. The hide and extract process always happens in your browser.
Happy to answer any questions about how it works or the design decisions behind it.
You're right. In Standard Mode, FileVeil appends encrypted data to the end of the cover file. It's simple and broadly compatible because standard applications ignore trailing data.
For users who need stronger concealment, Pro+ includes Stealth Mode, which uses a format aware embedding approach instead. In Stealth Mode, no payload is appended after the file's normal end, and the original cover file can be restored to its exact original state at any time.
Happy to answer any questions about how it works or the design decisions behind it.
For users who need stronger concealment, Pro+ includes Stealth Mode, which uses a format aware embedding approach instead. In Stealth Mode, no payload is appended after the file's normal end, and the original cover file can be restored to its exact original state at any time.