Last month, Google released a beta version of its desktop search software: Google Desktop Search. Install it on your Windows machine, and it creates a searchable index of your data files, including word processing files, spreadsheets, presentations, e-mail messages, cached Web pages and chat sessions. Its a great idea. Windows searching capability has always been mediocre, and Google fixes the problem nicely.
There are some security issues, though. The problem is that GDS indexes and finds documents that you may prefer not be found. For example, GDS searches your browsers cache. This allows it to find old Web pages youve visited, including online banking summaries, personal messages sent from Web e-mail programs and password-protected personal Web pages.
GDS can also retrieve encrypted files. No, it doesnt break the encryption or save a copy of the key. However, it searches the Windows cache, which can bypass some encryption programs entirely. And if you install the program on a computer with multiple users, you can search documents and Web pages for all users.
GDS isnt doing anything wrong; its indexing and searching documents just as its supposed to. The vulnerabilities are due to the design of Internet Explorer, Opera, Firefox, PGP and other programs.
First, Web browsers should not store SSL-encrypted pages or pages with personal e-mail. If they do store them, they should at least ask the user first.
Second, an encryption program that leaves copies of decrypted files in the cache is poorly designed. Those files are there whether or not GDS searches for them.
Third, GDS ability to search files and Web pages of multiple users on a computer received a lot of press when it was first discovered. This is a complete nonissue. You have to be an administrator on the machine to do this, which gives you access to everyones files anyway.
Some people blame Google for these problems and suggest, wrongly, that Google fix them. What if Google were to bow to public pressure and modify GDS to avoid showing confidential information? The underlying problems would remain: The private Web pages would still be in the browsers cache; the encryption program would still be leaving copies of the plain-text files in the operating systems cache; and the administrator could still eavesdrop on anyones computer to which he or she has access. The only thing that would have changed is that these vulnerabilities once again would be hidden from the average computer user.
In the end, this can only harm security.
GDS is very good at searching. Its so good that it exposes vulnerabilities on your computer that you didnt know about. And now that you know about them, pressure your software vendors to fix them. Dont shoot the messenger.
Bruce Schneier is CTO of Counterpane Internet Security Inc. Free Spectrum is a forum for the IT community and welcomes contributions. Send submissions to firstname.lastname@example.org.