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Ubuntu / Debian Linux Find Weak OpenSSL keys

This bug really was a bad one. I've client with over 200 Debian Linux server. Updating all systems wasn't the problem. With the help of Cfengine I was able to push updates but managing all workstation ssh keys (over 1000+ Windows and Linux/BSD workstations) and testing everything took so much time. Debian shouldn't have modified the package in first place. I also had to upgrade over 30 SSL certificates and a whole new CA for OpenVPN. Luckily VeriSign is providing revocation and replacement of SSL certificates (generally it is not provided free of charge) till 30-June-2008.

How do I find out all weak keys?

You can check all your weak keys with following commands:
# wget http://security.debian.org/project/extra/dowkd/dowkd.pl.gz
# wget http://security.debian.org/project/extra/dowkd/dowkd.pl.gz.asc
# gpg --keyserver subkeys.pgp.net --recv-keys 02D524BE
# gpg --verify dowkd.pl.gz.asc
# gunzip dowkd.pl.gz
# perl dowkd.pl host localhost

You should see 0 weak keys. If you run Debian or Ubuntu Linux upgrade your OpenSSL and fix all the affected softwares. There is also wiki page that will address all your concerns. Overall it lasted for few days for large clients. How many hours did you spend updating Debian systems?

Download of the day: Unbound DNS Resolver

Unbound is a validating, recursive, and caching DNS resolver. The C implementation of Unbound is developed and maintained by NLnet Labs. It is based on ideas and algorithms taken from a java prototype developed by Verisign labs, Nominet, Kirei and ep.net.

Unbound is designed as a set of modular components, so that also DNSSEC (secure DNS) validation and stub-resolvers (that do not run as a server, but are linked into an application) are easily possible.

Download Ubbound

=> Visit the project web page to grab latest Unbound source code.