Passwords, redaction and PDF security

When to use it

Encryption, viewer permissions, unlock, irreversible redaction and factual security reporting without absolute claims. The situations below show when this guide can help you choose the right workflow and avoid unnecessary processing.

• You need to encrypt a separate copy with a known password.
• You need to irreversibly hide selected areas or inspect active content.

How it works

This guide divides the topic into three consecutive stages: choose the boundary, review losses, verify the result. Follow them in order to understand the result and the points that require manual review.

1. 01Choose the boundaryProtect limits opening a copy; redact removes selected data from the result.
2. 02Review lossesBefore a destructive operation, the UI lists properties that will not be preserved.
3. 03Verify the resultEncryption, redaction and security facts are independently checked before the artifact is released.

What changes

Before starting, identify which parts of the document will change and which will remain intact. The list below describes changes in the output copy rather than hidden modifications to the source file.

• Protect creates an AES-256 encrypted copy.
• Unlock creates a separate unencrypted copy after the correct password.
• Redaction rebuilds the entire result from sanitized raster pages.

What can be lost

Some operations affect more than the visible page and can change text layers, forms, links or signatures. This list helps you decide whether the separate output copy is suitable for the next stage of your work.

• Raster redaction removes searchable text, forms, links, actions, attachments and metadata, and invalidates digital signatures.
• Unlock creates a new copy and does not preserve the trust of a source digital signature.

Limitations

Limitations describe the current implementation boundary and the cases that require additional review. Check them before uploading, especially when a document is complex, protected or contains important structure.

• Viewer permissions are not DRM.
• Unlock works only with a known password and does not attempt recovery.
• A security report checks known facts but does not certify the absence of every risk.

Related tools

Related tools let you move directly from the explanation to the appropriate action. Each tool uses its own workflow and shows its specific limits before processing starts.