Can Someone Upload Business Files Without Being Traced

Is the origin of a file traceable? If it is how can I sanitise it?

The brusk answer is information technology depends:

• If the file contained your proper noun, accost, telephone number, and social security number it would not be very difficult to trace information technology back to y'all ...

• A lot of applications get out identifying data of some kind - known equally Metadata - in files in addition to the obvious visible information in the file itself.

• Metadata can usually be removed from files (the removal method depends of the type of the file).

• Uploading a file volition send only the primary data stream, and leave alternating data streams and filesystem-resident metadata backside.

• As pointed out by Andrew Morton some organisations make minor grammatical (or other) changes to each copy of a document before it gets distributed.

  Past doing this copies can be tracked to particular individuals if the re-create gets stolen (or passed on). This, of form, is very hard to defeat.

• Read on for more information about the kind of sensitive and hidden data that can be associated with different kinds of files and how to clean (sanitise) them.

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Are patently text files condom to employ?

As pointed out by Uwe Ziegenhagen, even Windows plain text files (as well as any other file type) on a NTFS file system can potentially incorporate metadata, in the form of Alternate Data Streams. See likewise How To Use NTFS Alternate Data Streams.

Alternating data streams permit files to be associated with more than one data stream. For example, a file such as text.txt can have a ADS with the name of text.txt:undercover.txt (of course filename:ads) that can only be accessed past knowing the ADS name or past specialized directory browsing programs.

Alternate streams are not detectable in the original file's size but are lost when the original file (i.e. text.txt) is deleted, or when the file is copied or moved to a partitioning that doesn't back up ADS (e.k. a Fat partition, a floppy disk, or a network share). While ADS is a useful feature, information technology can also easily eat up hd space if unknown either through being forgotten or not being detected.

This feature is just supported if files are on an NTFS drive.

Source UltraEdit File Open Dialog.

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Viewing and Deleting Alternate Data Streams

Notes:

• Any file on an NTFS file system can accept an alternating data stream attached to it (not only text files).
• For more data well-nigh the potential security issues associated with alternate data streams run across Hidden Threat: Alternate Information Streams

Notepad and and Give-and-take tin exist used (from the command line) to open and read alternating data streams. Run into this reply NTFS alternating data streams by nishi for more information.

UltraEdit can open up alternate data streams from within the program itself.

AlternateStreamView tin can be used to delete alternating data streams:

AlternateStreamView is a small utility that allows y'all to browse your NTFS bulldoze, and find all subconscious alternate streams stored in the file organization.

Later on scanning and finding the alternating streams, you can extract these streams into the specified binder, delete unwanted streams, or save the streams listing into a text, HTML, CSV or XML file.

Source AlternateStreamView by Nirsoft

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How most images?

As pointed out by Scott, images can besides contain curtained information (a file, message, some other paradigm, or a video, using steganography:

Steganography includes the concealment of information within computer files. In digital steganography, electronic communications may include steganographic coding inside of a transport layer, such equally a document file, image file, program or protocol.

Media files are ideal for steganographic transmission because of their large size. For example, a sender might start with an innocuous paradigm file and adapt the color of every 100th pixel to correspond to a letter in the alphabet, a change so subtle that someone non specifically looking for it is unlikely to notice it.

Source steganography

This, of grade, is very hard to remove.

See also Steganography - A Information Hiding Technique and Stenography Software

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What virtually Excel spreadsheets or Word documents?

By default office documents comprise personal data:

• This information tin can be removed, see the link beneath.

Discussion:

• Consider using a evidently text file, created with notepad or other editor, instead of a word certificate

Spreadsheet:

• Consider using a CSV file, created with excel and saved as CSV, or create a CSV directly with another program such every bit notepad.

Give-and-take documents can contain the following types of hidden information and personal information:

• Comments, revision marks from tracked changes, versions, and ink annotations

  If you lot collaborated with other people to create your document, your document might contain items such as revision marks from tracked changes, comments, ink annotations, or versions. This information tin enable other people to run across the names of people who worked on your document, comments from reviewers, and changes that were fabricated to your certificate.

• Certificate backdrop and personal information

  Certificate properties, besides known as metadata, include details near your certificate such as writer, subject, and title. Document properties also include information that is automatically maintained by Part programs, such as the name of the person who most recently saved a document and the appointment when a document was created. If you used specific features, your document might likewise incorporate additional kinds of personally identifiable information (PII), such every bit e-postal service headers, send-for-review data, routing slips, and template names.

• Headers, footers, and watermarks

  Word documents tin contain data in headers and footers. Additionally, y'all might accept added a watermark to your Word certificate.

• Hidden text

  Word documents tin can contain text that is formatted as hidden text. If you practice not know whether your document contains hidden text, you can use the Document Inspector to search for it.

• Document server properties

  If your certificate was saved to a location on a document management server, such as a Document Workspace site or a library based on Microsoft Windows SharePoint Services, the document might contain additional document properties or data related to this server location.

• Custom XML data

  Documents can contain custom XML data that is non visible in the document itself. The Document Inspector can observe and remove this XML information.

Note:

• The Word Document Inspector won't detect white-colored text or images with steganography (a concealed a file, bulletin, image, or video)

Source Remove subconscious information and personal information past inspecting documents

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What if I use a PDF file, obtained from someone else?

PDFs are not safe:

• They tin can incorporate viruses, meet Tin a PDF file incorporate a virus?

• They can contain JavaScript. If the JavaScript was to "phone home" every time the PDF was opened there could be a nice trail including your IP address.

• PDFs can also contain hidden information:

  PDF has also been frequently used as a distribution format for files originally created in Microsoft Office because hidden data and metadata tin can exist sanitized (or redacted) during the conversion process.

  Despite this common use of PDF documents, users who distribute these files oft underestimate the possibility that they might contain subconscious data or metadata. This certificate identifies the risks that can be associated with PDF documents and gives guidance that tin can assistance users reduce the unintentional release of sensitive data.

Source Hidden Data and Metadata in Adobe PDF Files:
Publication Risks and Countermeasures, a certificate written by the NSA

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How can I check the PDF file to make certain information technology doesn't contain any sensitive information?

You tin can follow the advice given by the NSA to sanitise your PDF.

• I have summarised the basic steps you need to follow.
• Detailed step by step instructions with screen shots are available from the link beneath.

This paper describes procedures for sanitizing PDF documents for static publication. Sanitization for the purpose of this document means removing subconscious information and dynamic content not intended for publication (for example, the username of the author or interim editing comments embedded in the file but not visible on any pages).

Hidden data includes:

• Metadata

• Embedded Content and Attached Files

• Scripts

• Hidden Layers

• Embedded Search Index

• Stored Interactive Form Information

• Reviewing and Commenting

• Hidden Page, Prototype, and Update Data

• Obscured Text and Images

• PDF (Not-Displayed) Comments

• Unreferenced Data

...

Detailed Sanitization Procedure

1. Sanitize Source File

   If the application that generated the source file has a sanitization utility, information technology should be applied before converting to PDF.

2. Configure Security Settings

   • Ensure that all applicable Acrobat updates have been downloaded and installed
   • Disable JavaScript
   • Verify that the trust manager settings are fix accordingly

3. Run Preflight

   Preflight ensures that the file contents are compatible with the destination version, and applies 'fixups' every bit necessary.

4. Run the PDF Optimizer

   • If the PDF file contains other attached files, a warning message appears. Click 'OK' to go on. The fastened files will be removed during PDF optimization.
   • Document tags pose a subconscious information risk. This procedure (specifically the checked pick for 'Discard certificate tags') removes them from the sanitized PDF.

5. Run the Examine Document Utility

   • This helps to find text subconscious backside objects as well as whatsoever other areas that might have been missed in the previous steps.

Source Hidden Data and Metadata in Adobe PDF Files:
Publication Risks and Countermeasures, a certificate written by the NSA

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But I have antivirus software!

Even antivirus software is not guaranteed to catch everything. Come across zilch day exploit:

A zero-twenty-four hour period (also known every bit goose egg-hour or 0-day) vulnerability is a previously undisclosed computer-software vulnerability that hackers can exploit to adversely affect reckoner programs, data, additional computers or a network.

It is known as a "zero-24-hour interval" considering once the flaw becomes known, the software'southward writer has goose egg days in which to plan and advise whatsoever mitigation against its exploitation (for instance, by advising workarounds or by issuing patches)

Source zero day

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What about my USB drive? Do I need to worry about that?

You cannot guarantee your USB flash drive is safe.

USB peripherals, such as pollex drives, can be reprogrammed to steal the contents of annihilation written to the drive and to spread the firmware-modifying code to any PCs it touches. The net result could be a self-replicating virus that spreads through sparing pollex drives, much like the rudimentary viruses that spread by floppy disk decades agone.

Source Why your USB device is a security hazard

amidonthedusbame.blogspot.com

Source: https://superuser.com/questions/1030325/is-the-origin-of-a-file-traceable-if-it-is-how-can-i-sanitise-it

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