comp.security.unix and comp.security.misc FAQ
Frequently Asked Questions on comp.security.unix and comp.security.misc.
This FAQ about comp.security.unix and comp.security.misc
was compiled and written by Alan J Rosenthal flaps@dgp.toronto.edu
with numerous contributions by others.
01 This faq (comp.security.unix and comp.security.misc)- This is not supposed to be a statement of group consensus. This is ...
02 Can anyone here tell me how to exploit the [whatever] bug? or Can anyone here tell me how to break in to my ISP?- No. We're security professionals. We try to secure systems. We think ...
03 What do the "identd" lines in my syslog mean? Is this a security exposure? Can I turn off identd?- Discarding the timestamp and hostname, the lines look something like this:...
04 I just noticed that [something]. Has my machine been compromised?- Maybe. You probably don't know whether it always was like this. You ...
05 What does port number [whatever] mean?- RFC 1700 is obsolete. The standard current reference ...
06 Here's new, unbreakable encryption software.- It's probably not substantially new, and I'm sure it's not unbreakable....
07 What should I read to learn how to secure my computers? What should I read to learn about computer security?- The number one thing to do is to install all of your vendor's ...
08 Is there a newer version of cops?- No. Version 1.04+ is a bit old but performs some functions which are still ...
09 Tripwire fails the self-test, dumps core when building the database, and dumps core when verifying.- Fails the self-test (on fast machines):...
10 Cops won't "make" in some versions of linux (GNU).- Remove the '#' from BRAINDEADFLAGS in the makefile....
11 Various problems with building anything under Solaris, especially "/usr/ucb/cc: language optional software package not installed".- This is not a security question. Please ask in a solaris newsgroup instead,...
12 What's that weird URL with SATAN/SAINT? I'm not running a web server! or SATAN says "Can't find my own hostname".- SATAN acts as a web server so that it can use HTML conveniently. The ...
13 SATAN doesn't display right in my web browser; it asks me to save the file.- Newer web browsers seem to use different algorithms in guessing mime ...
14 How do I find all setuid and setgid files?- find / -local -type f \( -perm -4000 -o -perm -2000 \) -...
15 Tcp wrappers (tcpd) thinks all hosts are 0.0.0.0 in Solaris 8 or in some versions of AIX.- This is because the line for that service in inetd.conf still says tcp6....
16 I can't get .rhosts/.shosts to work with ssh.- If ssh doesn't do what you want, the output of ssh -v may be helpful....
17 Should I block all ICMP at my firewall/router?- No. You need to allow the can't fragment message through or you will ...
18 How do I prevent my machine from announcing OS version, daemon version, etc in the banner message?- In unix, find the daemon in question, possibly by finding its ...
19 How do I recover from forgetting my root password? (Similarly: I messed up the root line in /etc/passwd and can't su or login as root; what do I do?)- Basically, you want to boot from CD/floppy or in single-user mode....
20 Is a portscan of a machine malicious/illegal/unfriendly?- This is included here because it's a recurring flamefest. Please ...
21 Can my ISP/employer monitor [various things I'm doing]?- Do they have the technical ability? Yes. Your packets go through ...
22 Why do some people get so upset when system penetration is called "hacking"?- The word hacker has a long and honourable tradition of referring to ...