There are many Debian bugs in bugtraq does this mean that it is very vulnerable?
Debian contains quite a number of packages and different software, probably more that provided by some propietary operating systems. This means that there might be lurking more potential security issues than in systems with less software. However, there are many advisories related to source code audits done to major software components included in Debian. Whenever such source code audit turn out a major flaw it is fixed and a advisory is sent to list such as bugtraq. Bugs that are present in the Debian distribution usually affect other vendors and other distributions as well. Check the “Debian specific: yes/no” part on top of each advisory (DSA). If there is a “yes”, it only affects Debian, if there is a “no” it probably also affects other distributions as well. Debian contains quite a lot of packages, and nowadays there are many groups looking for security problems in software (for whichever reasons).
The Debian distribution boasts a large and growing number of software packages, probably more than provided by many proprietary operating systems. The more packages installed, the greater the potential for security issues in any given system. More and more people are examining source code for flaws. There are many advisories related to source code audits of the major software components included in Debian. Whenever such source code audits turn up security flaws, they are fixed and an advisory is sent to lists such as Bugtraq. Bugs that are present in the Debian distribution usually affect other vendors and distributions as well. Check the “Debian specific: yes/no” section at the top of each advisory (DSA).