Thomas Futschek wrote:
Recently I saw if you boot a kernel with a boot option like 'init=/bin/bash' (to example: linux init=/bin/bash) you become root without athentification.
Can anybody tell me why it works and how I protect?
init=/bin/bash uses a shell instead of the normal init process. This is comparable to booting a rescue system, only that you you use your own installed system instead of a floppy/CD-ROM/DVD. Protect by using the password= and restricted lilo.conf options and using 600 permission for the lilo.conf file. Further protection against using rescue systems: change your BIOS boot sequence to boot only from hard disk and use a BIOS password (this is only a simple protection, people with physical access to the system can do anything from resetting the BIOS to taking out the hard disk - only a crypted file system will help there) Kevin -- _ | Kevin Ivory | Tel: +49-551-37000041 |_ |\ | | Service Network GmbH | Fax: +49-551-3700009 ._|ER | \|ET | Bahnhofsallee 1b | mailto:Ivory@SerNet.de Service Network | 37081 Goettingen | http://www.SerNet.de/