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That takes care of the layering issue, but the blur / pixellation etc can still be undone in many cases. Take a look at the link about “swirl face”.

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rc primak

Thanks for the great article.

I do wish you had gone into a bit more depth regarding privacy and data redaction. In fact, I’d love to see an Ask Woody article on safe redaction methods and tools.

Getting redaction right can be tricky.

It’s unlikely that blurring or pixelation will thwart a determined attacker.

When modifying the screenshot image for privacy, it’s important to use a tool that actually removes the sensitive information so that it doesn’t remain in the file. Blurring, pixelation, and “swirl” can all be reversed to a surprising extent. Remember the infamous “swirl face”.

Even covering the data with an opaque black box may not be enough. Some image editors layer the redacting black box on top of the data in such a way that the original data remains in the file.

Here are a few relevant links

https://matzjb.se/2015/07/26/deconstructing-swirl-face/

https://www.wired.com/story/redact-pdf-online-privacy/

https://www.bleepingcomputer.com/news/security/researcher-reverses-redaction-extracts-words-from-pixelated-image/

https://arstechnica.com/information-technology/2017/02/google-brain-super-resolution-zoom-enhance/

https://www.adobe.com/acrobat/hub/how-to-remove-redactions-pdf.html

Larry

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ibe98765, rc primak, windbg

Added both *.zip and *.mov to pihole’s domain block list

I’ve found that I can work around the issue by adding local addresses explicitly to the hosts file, c:\windows\system32\drivers\etc\hosts

192.168.1.1   myrouter

and then browsing to https://myrouter/

 

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GoneToPlaid, Karlston, HiFlyer, gborn, woody