Security & privacy
PDF encryption: AES-256 vs RC4
Not all "encrypted" PDFs are equally safe. The algorithm decides whether protection is real or theatre.
RC4 is obsolete
Older PDFs used RC4, which is now considered broken. A file protected only by RC4 should be treated as effectively unprotected for anything sensitive.
AES-256 is the standard
Modern PDFs use AES-256, the same class of encryption trusted for government and banking data. It is the right choice for confidential documents.
How to check
Re-encrypt older files with a current tool to upgrade them to AES-256, rather than trusting decades-old protection.
In FreshPDF
FreshPDF's protect tool always uses AES-256 — re-save an old file through it to upgrade its encryption.
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