Select an Office File to Audit & Sanitize
Supports Microsoft Word (.docx), Excel (.xlsx), and PowerPoint (.pptx).
Why Office OpenXML Files Silently Leak Corporate Data
Modern Microsoft Office files (.docx, .xlsx, .pptx) are zip packages containing XML data streams. When you save a document, Office automatically records your local workstation username, internal network paths, and total editing time inside the document properties.
The <Template> tag frequently stores full Windows directory paths (e.g. C:\Users\jdoe\AppData\Roaming\...) or active directory UNC paths (\\corp-file01\templates\), exposing organizational usernames and network layouts.
Total editing time (<TotalTime>) and revision numbers (<revision>) allow opposing legal counsel or forensic auditors to prove whether a document was drafted in haste, backdated, or edited after a specific event.
Commercial office conversion sites require uploading sensitive legal briefs and financial spreadsheets to remote servers. OverlayCheck unzips, sanitizes, and repacks files strictly in browser memory.