Privacy concerns over popular ShowIP Firefox add-on

A popular Firefox add-on appears to have started leaking private information about every website that users visit to a third-party server, including sensitive data which could identify individuals or reduce their security.

Naked Security reader Rob Sanders alerted us to the activities of the recently updated ShowIP add-on for the Firefox browser.

According to the description on the Mozilla add-ons website, ShowIP is designed to “show the IP address(es) of the current page in the status bar. It also allows querying custom information services by IP (right click) and hostname (left click), like whois, netcraft, etc. Additionally you can copy the IP address to the clipboard.”

Currently over 170,000 people are said to be using ShowIP.

What the add-on’s description doesn’t say is that since version 1.3 (released on April 19th 2012) it has also sent -…

Read more in my article on the Naked Security website.

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Graham Cluley •   @gcluley

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, on Mastodon at @[email protected], or drop him an email.