Tuesday, March 30, 2010

"An error occured in avast! engine: Invalid argument"

This annoying message popped up after I ran the update in avast! in Ubuntu yesterday. avast! crashes every time I attempt to launch it after that. Did some googling and someone suggested deleting a file called "400.vps" in the ".avast" folder. I did just that and avast! was able to launch again. However, the same error occurs immediately after the virus definition update is performed. There is an error with the signature file. Hmmmmmm. What happened to quality control nowadays?

Update: I resolved the update issue. Run the following command.

commandrine@bridge:/$ sudo sysctl -w kernel.shmmax=128000000
kernel.shmmax = 128000000
commandrine@bridge:/$

I combined this command and the avast! update command together in this script to simplify matters. You no longer need to launch the avast! GUI to start the update. Download it here.

Friday, March 12, 2010

Justified

Adobe Reader is officially the most exploited software. My decision to remove Adobe Reader from my machines years ago is now fully justified and not a choice out of paranoia. In 2nd place is Microsoft Word which is also not installed on any of my systems at home.
A case of security by obscurity? Why do soldiers wear camouflage when they can be killed by weapons of mass destruction?

Monday, March 8, 2010

Kon-Boot

I have demonstrated password reset and cracking of Windows passwords before. I won't even bother demonstrating resetting of Mac OS X passwords because it is so trivial. Lame Apple ships a password reset utility with their Mac OS X installer DVD. DUH!!!
Kon-Boot is a powerful tool that gives you root privileges on Linux and administrator rights on Windows without needing to crack or know the admin password.
In my demo, I burnt Kon-Boot as a bootable disc and booted up my Linux system with it. Kon-Boot modifies my Linux kernel and permits me to gain root access just by entering "kon-usr". I run the "whoami" command to prove that I am logged in as root without entering the root password.
The high res version of this demo can be downloaded here.