New ask Hacker News story: Barracuda VPN on Linux permanently and silently changes resolv.conf

Barracuda VPN on Linux permanently and silently changes resolv.conf
4 by Max-Ganz-II | 0 comments on Hacker News.
I work occasionally, as an IT contractor. I recently completed a contract for a large German company, who will remain nameless. Nice bunch, nothing wrong with them, and I would not want to embarrass them. Said company provides to its remote staff a VPN, Barracuda VPN, and the VPN is available for Linux, which in my case means a Debian package. I installed, never needed it, six months later contract complete uninstalled. A few months after this, I stumbled across the fact that my resolv.conf had been altered, to that given below, and not reverted by uninstallation; nameserver [German company DNS IP #1] nameserver [German company DNS IP #2] nameserver 127.0.0.1 nameserver ::1 search [an IP name from German company] The VPN installer had prepended its DNS to resolve.conf I may be wrong, but I understand resolv.conf uses servers in the order they are given, and uses only the first three servers. (The final line, "search", causes any DNS IP name lookup which fails to be retried with the given IP name appended.) These behaviours occur whether or not the VPN is active, and where resolv.conf was not reverted by uninstallation, continue occurring after the VPN is uninstalled. I contacted Barracuda about this matter, explaining and questioning what had happened. The initial reply was prompt, and asked for a serial number. I replied I had never been given a serial number, just the package, and I had left the company concerned some months before (and of course, had only noticed this problem afterwards, as it is a silent and unexpected change). There was no reply, but since then, I've received automated emails telling me I have a ticket, and that it is awaiting a serial number (to which I have replied, to no effect or response). Barracuda have a second email address, for security issues. Email to this address has gone unanswered.