Content related to computer security., i.e. content about policies, mechanisms, etc. needed make sure data is not leaked or corrupted and services available in all circumstances.

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5
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2answers
124 views

Is it more dangerous to connect to the net as root?

If I make some kind of tcp connection to the net as root, is that less safe then making the same tcp connection as a normal user? I have been suspecting for a while that by making a connection as ...
8
votes
1answer
2k views

How to stop users from Switching to Root user

I have disabled the root user login from Sshd.conf file so now no one can login using root user even if they know the password SOMEHOW. Now I have 3 users in server ROOT,EMERG and ORACLE. I want to ...
2
votes
1answer
461 views

Running a local port scan and found open ports but, don't know what they're used for?

I wrote a very basic python script to port scan my system. I'm running linux-mint lisa: open_ports = [] for port in xrange(65536): conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM) ...
3
votes
1answer
555 views

What should I check after an unauthorized access?

I accidentally left an open port on my router, leaving access to one of my computers via SSH, using a rather insecure password. I noticed because I checked /var/log/auth.log and there is just one ...
1
vote
3answers
63 views

execute file in server more safely?

We have a application which takes a C++, C, or Java file as input, executes it, and displays the output to the client. What are the best measures that can be taken so that no security related issues ...
5
votes
3answers
693 views

Why does time/ident/daytime/comsat run after an OpenBSD 5.2 install?

I installed an OpenBSD 5.2 using "-* & +etc* & +base* & +bsd". After finished with the install, I rebooted, then netstat -at | grep LISTEN, this is what I get for output: Why does so ...
9
votes
1answer
729 views

How can I limit ssh *remote* port forwarding?

I need to limit which ports can be remotely 'ssh -R' forwarded by an user. I know about permitopen option on authorized_keys, but as it says on man page it only limits local 'ssh -L' port forwarding ...
4
votes
3answers
1k views

Is it impossible to run as `root` if the machine isn't rooted?

By default, the user of the device does not have access to certain root objects (e.g. the /data directory). Even though these objects are off-limits, however, it would seem to me that these objects ...
4
votes
2answers
451 views

How to lock a directory?

I want to block any kind of access to a certain directory unless a password is provided. It could be my root or account password. The directory is residing on an NTFS partition, and this method needs ...
0
votes
0answers
49 views

Ossec Installation Error

While installing Ossec Hids 2.6 on Redhat 5.5 installed on Virtual Machine, I got this error message. Whats wrong here.
1
vote
1answer
95 views

keeping keys on an auxiliary removable drive

It seems that servers are only as secure as the machine that holds the keys and that in turn means the desktop/screensaver password is the line of defence for not only the desktop itself but any ...
1
vote
0answers
703 views

Using Metasploit with 3G USB modem

I have a computer with Linux BackTrack 5 as host and Windows XP as guest on virtual box. I am using Host-Only-Adapter to create virtual LAN and to share USB modem internet as well so that both host ...
-1
votes
1answer
2k views

What is the security impact of not using tls-remote with OpenVPN

Is it a security issue not using the tls-remote option in OpenVPN? That is not verifying the server's common name. Is a MITM attack possible? Could this be an issue, especially with services like ...
1
vote
1answer
152 views

Accounts attacked

I have run two commands below. I find some of the accounts attack as below. I do not have the account test,teste,oracle and admin in my home directory. As there system account. How to know which are ...
2
votes
3answers
1k views

How can I securely login remotely to my Linux box over the internet?

I'm pretty much a Linux beginner, but this question has been on my mind. What's the simplest, most secure way to connect to my computer at home from work or from the library, &c? I'm running Mint ...
2
votes
2answers
1k views

Moving a root directory to a separate partition

I'd like to create a new partition and move the contents of the /var directory to it for the security reason of having /var/www and other subdirectories "mounted" with nosuid, noexec, and nodev ...
1
vote
1answer
1k views

add members of wheel group, sudo access

On Fedora15, following this wiki, I added a user to wheel group, which is already in the sudoer config file. but still I get not-a-sudoer error prompt. Should I specifically name every member of a ...
38
votes
4answers
32k views

What is the point of sshd “UseDNS” option?

I know what it does, but i don't know why. What attack(s) does it prevent ? Is it relevant for all kind of authentication methods ? (hostbased, password, publickey, keyboard-interactive ...)
0
votes
4answers
751 views

securing SSH and disabling direct root

In these instructions below what appears on my terminal is different so not sure what I should change. After port 22 mine says #AddressFamily any and further down for protocol it has longer line ...
0
votes
0answers
79 views

Usage of stunnel for configuring secure services as a default?

Ok, I am aware nothing will beat manual security configuration through your standard daemon config files, but is it bad practice to configure stunnel for all services on say, a production ...
-2
votes
2answers
117 views

What software(s) should I install on new system(with Linux as a OS) to prevent it from getting hacked? [closed]

I am switching to new system with a OS using Linux.I will be using another system which has windows ultimate which is hacked.I am being cyber bullied. I have given a reference to this as a question on ...
2
votes
0answers
3k views

How can I connect to a wireless network with hidden SSID using the terminal? [closed]

I'm starting to learn about wireless pentesting with BackTrack, and while learning how to find out the hidden SSID I wondered how could I connect to the wireless network after I discover the SSID. The ...
12
votes
6answers
56k views

How can I monitor all outgoing requests/connections from my machine?

My machine is a server so I want to ignore connections being made to my server (e.g. when someone visits my website). I want to see only connections/requests being made by my server to other places. ...
3
votes
1answer
78 views

How is the inherited file descritor vulnerability dealt with in Unices?

Ulrich Drepper describes a vulnerability in programs that have open file descriptors then they fork() and execve() without lots of very careful locking in place. He also talks about new kernel ...
3
votes
2answers
877 views

Is TRESOR included in the latest kernel?

Did TRESOR get included in the mainline Linux kernel? Where would I look to find out? Is there any documentation describing its use? Reading about cold boot attacks on Wikipedia makes me think TRESOR ...
1
vote
1answer
324 views

How to export a private PGP email key

I have made a keypair for my email address using gnupg. I thought that I should probably keep a backup of it so that if I lose my desktop computer I can continue using the same key. Is this the ...
0
votes
1answer
215 views

Intruder nature detection by opensource tools like tripwire

I want to use different kind of intrusion detection tools like OpenSource Tripwire. Please suggest me some tools which can provide me some additional information to that provided by tripwire? ...
2
votes
2answers
79 views

Checking integrity of my server data

I want to make a log to detect the nature of intrusions into my Unix/Linux based server. For that I want to learn some tools like Open Source Tripwire and OSSEC. Please suggest to me similar tools. ...
2
votes
1answer
2k views

Is there a way to report incorrect login attempts in Ubuntu 12.10?

I am concerned with some people trying to access my laptop while I am away in my work place. Therefore I was wondering if is there a way to set up kind of automatically monitor and report wrong ...
3
votes
1answer
1k views

How to replace setuid with file-system capabilities

Inspired by this question here is the follow-up: As some of you may know setuid-binaries are dangerous, since some exploits use these to escalate their rights up to root. Now it seems that there has ...
2
votes
1answer
142 views

is it secure /not dangerous to ssh with keys through public transparent proxy?

I use pub key for ssh. Is it normal practice to connect to own server through public proxy? I think with plain pass it is surely dangerous but how about RSA keys?
5
votes
3answers
2k views

Stracing su and ssh shows the password. Is this a security flaw or am I missing something?

I'm currently fascinated by strace so, being new to it, I decided to play around a little. As suggested by the question title, I tried both strace su and strace ssh. Both commands displayed the ...
4
votes
3answers
1k views

rsync server/daemon security

I have a NAS (Netgear Readynas NV+) at home and a linux (Arch) box at work that is always on. The linux box is already running an ssh server/daemon and the NAS is already running an rsync ...
2
votes
0answers
215 views

How many rings does OpenBSD use?

Usually a Windows/Linux operating system uses afaik max 2 rings But how many rings does OpenBSD use?
3
votes
1answer
3k views

How to ensure that anonymous FTP has been disabled on a Solaris 10 system?

What line in which configuration files in the /etc/ftpd directory do I have to check to ensure that anonymous FTP has been disabled? From my understanding now, to ensure that anonymous FTP is ...
1
vote
0answers
92 views

Running Tomcat MySQL and Apache under a group

I am trying to set up a web server at home using Ubuntu, but prefer my bash scripts to be platform agnostic hence why I am asking here. I also dislike apt-get everything. I am trying to create a ...
5
votes
2answers
430 views

What does “Do you expect to run the X Windows System?” do when installing OpenBSD?

When installing OpenBSD 5.1, I got the question: Do you expect to run the X Windows System? What change does the installer make to my system if I say "yes"? I know what X Windows is, but I don't ...
2
votes
1answer
368 views

How to move the /var/www directory to a USB HDD?

I have a default OpenBSD 5.1 install. How Can I enabled httpd, OK. QUESTION: How can I use the /dev/sd0a on /mnt/usbhdd type ffs (local, nodev) instead of the default "/var/www" directory? What ...
5
votes
2answers
930 views

How to disable login for an user?

My Linux has many not-human users like cron, ntp, daemon, http, etc. I want to disable anybody to login as any of this users. Real people on my machine are root and me, so only root and me should be ...
5
votes
3answers
293 views

Are sudo and gksudo safe?

I noticed after running a sudo command in terminal or running a administrative application that uses gksudo, it won't ask again for the password for a time (something like 5 minutes). Now let's ...
3
votes
1answer
1k views

How to disable remote access on a linux distribution?

So I've read in Mark Sobell's book on Linux, that Linux by default is open to remote administration. Now seen as I'm running a Fedora 17, on a laptop I never have to administrate anything on remotely, ...
5
votes
1answer
769 views

What are EXT4 Security Labels?

During Gentoo installation of Gnome keyring, I am told to switch on EXT4 Security Labels, which is described in the kernel documentation by: Security labels support alternative access control ...
3
votes
2answers
365 views

why slight delay after failed login in tty [duplicate]

Possible Duplicate: Why a wrong password gives a big delay Whenever I mistype my password when logging in in a tty, I have noticed that I have to wait for a second before I'm able to log in ...
8
votes
1answer
210 views

How to use /etc/fbtab in OpenBSD to secure X11?

OpenBSD's man page afterboot(8) suggests: "You might wish to tighten up security more by editing /etc/fbtab as when installing X." How might one do this? What lines when added to /etc/fbtab would ...
6
votes
2answers
5k views

Iptables: matching outgoing traffic with conntrack and owner. Works with strange drops

In my iptables script I have been experimenting with writing as finely grained rules as possible. I limit which users are allowed to use which services, partly for security and partly as a learning ...
3
votes
1answer
534 views

Why is it a bad idea to run as root? [duplicate]

Possible Duplicate: Concern about logging in as root overrated? I often hear that it's a bad idea to use root for general use. Why is this a bad idea?
2
votes
1answer
246 views

Security drawbacks of disabling tty password check

I found that, in /etc/inittab, this modification (-a username) for the user u disables the login/password check for all tty:s: 1:2345:respawn:/sbin/getty -a u 38400 tty1 2:23:respawn:/sbin/getty -a u ...
1
vote
1answer
318 views

For an init.d startup script, what is the ideal user to use as the owner of that process

Everyone says that running processes as root is bad, since it defeats the security and privileges model. But what user should be used to run a startup process? Is it really necessary to create a new ...
5
votes
1answer
820 views

root owned program with setuid bit on

Ping is a a program owned by root with the user id bit set. $ ls -l `which ping` -rwsr-xr-x 1 root root 35752 Nov 4 2011 /bin/ping As I understand it, if a user runs the ping process, then the ...
0
votes
1answer
78 views

What to make of system scans reported by psad

My system logs show that psad detects scans like this every minute. psad: scan detected: 192.168.1.10 -> 192.168.1.1 udp: [53] udp pkts: 2 DL: 2 If the first address is mine, and the second ...