Fake black-box redactions
Looks for dark filled rectangle patterns alongside text drawing operators in decoded content streams.
PDF Redaction & Privacy Autopsy
Audit a PDF for black-box overlay redactions, searchable or invisible text, older incremental revisions, attachments, scripts, forms, comments, and hidden layers.
Evidence warning: A clean automated report cannot guarantee that every secret was removed. Legal, medical, HR, and disclosure documents still require an authorized human review and an approved redaction workflow.
Analyze a PDF
Maximum 10 MB. The API processes the file in memory and does not retain file content. Never upload confidential material unless your policy permits processing by this service.
What the analysis checks
Revision time machine
Counts end markers and /Prev chains that indicate incremental saves may retain superseded PDF objects.
Hidden content surfaces
Checks for invisible text modes, unapplied redaction annotations, optional layers, forms, comments, and embedded files.
Active document behavior
Flags JavaScript, launch, and automatic-open action markers that should not be present in a sanitized disclosure copy.
Forensic workflow
- 1
Analyze the exact PDF intended for release and preserve its SHA-256 report.
- 2
Treat overlay, revision-history, active-content, and attachment errors as stop-and-review findings.
- 3
Apply permanent redactions, remove hidden data, export a sanitized copy, and run the audit again.
Frequently asked questions
Why is drawing a black rectangle unsafe?
The original text can remain selectable, searchable, extractable, or recoverable from the PDF objects underneath the rectangle.
Can earlier versions remain inside one PDF?
Yes. Incremental saving can append changes and preserve older objects. A /Prev chain or multiple revision markers deserves review.
Can this recover every hidden word?
No. Encryption, unusual filters, malformed structures, images, and unsupported compression can prevent automated inspection.
Is this legal advice or a compliance certificate?
No. It is a technical triage report for an exact file hash, not legal advice or certification.