How NOT to redact a PDF – Nuclear submarine secrets spilled

Graham Cluley
@gcluley

If you’re an organisation that is making public an internal document, you best make sure that you have deleted or blacked out any personal, confidential or actionable information.

The act of obscuring the sensitive information is known as “redaction”, and – for obvious reasons – needs to be done properly if you care about privacy and avoiding a potentially damaging data leak.

In the old days – before PDFs and Word documents – you might have redacted a document with a thick black marker pen, ensuring that anyone who made a photocopy of the document wouldn’t be able to see the censored words. Things are different with electronic media, of course.

Unfortunately, time and time again we’ve seen sloppy security procedures make it far too easy for unauthorised parties to view information in electronic documents that should have been properly redacted.

The last example which has made…

Read more in my article on the Naked Security website.

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Graham Cluley is a veteran of the anti-virus industry having worked for a number of security companies since the early 1990s when he wrote the first ever version of Dr Solomon's Anti-Virus Toolkit for Windows. Now an independent security analyst, he regularly makes media appearances and is an international public speaker on the topic of computer security, hackers, and online privacy. Follow him on Twitter at @gcluley, or drop him an email.

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