Recently I had a discussion with someone about the security of various linux distributions where he claimed Debian stable to be very secure and that they use old versions where they backport all occurances of security issues. This is a common assumption, too bad that it's wrong.
I want to document this to demonstrate the dangerousness of opinions like »stay with the old software«, »never touch a running system« and alike that are not limited but often found in the Debian community.
I had a look at the security policy on a package recently very popular for it's vast number of issues, namely php. Their last php-update on php5 was in july. They have a heavily patched version of php 5.2.0 and according to their changelog the last thing they patched was CVE-2007-1864.
Now that probably means that CVE-2007-3996, CVE-2007-3378, CVE-2007-3997, CVE-2007-4652, CVE-2007-4658, CVE-2007-4659, CVE-2007-4670, CVE-2007-4657, CVE-2007-4662, CVE-2007-3998, CVE-2007-5898, CVE-2007-5899, CVE-2007-5900 are unfixed. Oh, and before you ask: This list certainly is incomplete, it's just what I found without much hassle.
Not only looking at php5, php4 is still officially distributed by many vendors, some hosters still use it. You can't really blame them, as php.net announced it to be supported until 2007-12-31. But that's theory, in fact, nobody looks if the various recent issues also apply to php 4, most recent advisories don't mention it. Fact is, at least CVE-2007-3378, CVE-2007-3997, CVE-2007-4657, CVE-2007-3998 also apply to php 4 and are unfixed in their latest release 4.4.7 (not neccessary to mention that they're not fixed in the debian stable php4 package).
If someone prefers to stay with old software, it's up to them. But be serious. It's probably a hell-job to get all the recent security issues in an app like php backported to some ancient version. A quick check showed me that debian isn't able to do that. If you can't do that, don't claim it's in any way »supported«. Because doing that put's other people in dangerous situations.