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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146 views

git and remote security with Encfs [duplicate]

Possible Duplicate: How do i encrypt git on my server? I wanted to create a user on my server to use as a private repository. I'd like the files to be encrypted. Encfs will timeout after ...
3
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1answer
119 views

Is it safe to leave a enc folder mounted?

I was looking at this and ecryptfs seems cool. I'd like to use it on my server to encrypt git pushes. I dont want to ssh in everytime to mount/unmount the encrypted folder. However once in a while ...
2
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4answers
817 views

How to guarantee the integrity of an OS?

In information security, integrity means that data cannot be modified undetectably. This answer raised my interest, of course, I want to guarantee the integrity of my OS, outlined here. ...
7
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4answers
360 views

How can I safely give a shell to somebody?

I have a question about giving a shell account to somebody. How safe is it? He could read /etc. How can I give a secured shell account that will only restrict the user to some bins and his own home? ...
7
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2answers
242 views

Hibernate and security considerations

How do Linux and OSX handle sensitive memory pages (e.g. cryptographic keys) when running OS is suspended to disk? If the memory image written is encrypted, how are its keys handled?
3
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1answer
2k views

Privoxy redirect rule for Wikipedia

I have a few Privoxy rules, that can redirect HTTP Wikipedia [en,de] traffic to HTTPS: (a little part from the "user.action" file) { ...
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2answers
689 views

Is there a Debian security APT repository that allows access via ftp?

If I want security updates for Debian, I add the following line to /etc/apt/sources.list: deb http://security.debian.org <codename>/updates main Is there a repository that allows the http to ...
14
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3answers
7k views

How should one set up full-disk encryption on OpenBSD?

Is there a preferred method to set up full-disk encryption under OpenBSD, similar to dm-crypt under Linux? I'm looking for full-disk encryption, as if someone were to steal my notebook they could ...
3
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1answer
3k views

Can a user with /sbin/nologin shell login through ssh?

Is it possible to ssh to a machine as a user with no valid shell (say, mail)? So far I cannot, and using the command below doesn't work: $ ssh mail@machine.local /bin/bash It will always say "This ...
3
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3answers
285 views

Turning an old computer into a network firewall

I have an old Dell Dimension with two ethernet cards, and I need to turn it into a firewall. I've tried FireStarter and IPCop, but I don't think I'm setting them up right. Here's the setup that I'm ...
11
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2answers
3k views

Does SELinux provide enough extra security to be worth the hassle of learning/setting it up?

I recently installed Fedora 14 on my home pc and have been working on setting up different server related features such as apache, mysql, ftp, vpn, ssh, etc. I ran extremely quickly in to a barrier ...
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2answers
805 views

make a 2nd root?

I was thinking, maybe i'd like to disable passwords for the root user and only use keys to log in. and if i need to login without keys have a 2nd user that is like root in everyway except has a ...
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2answers
312 views

What is the “Online Certificate Status Protocol”?

I use privoxy. In the user.action file i have a redirect rule and a few websites: { +redirect{s@http://@https://@} } .twitter.com .facebook.com Ok! it's working great, e.g.: if i visit any ...
3
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2answers
356 views

Recommended way to login to root?

After I found out hundreds of hacking attempts are made in a day I decided I want to disable logging in to root remotely via a password. But then I found I can't switch users in WinSCP so I can't ...
5
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2answers
6k views

How do I disable remote root login via ssh?

How do I disable remote root login via ssh? I want to log into my server (I use keys on my main comp) then su into root instead of access root directly. I am using Debian. I follow guides online ...
2
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3answers
1k views

Is there any chance that some of these processes are malicious?

My significant other and I are sometimes paranoid that a foreign government usually associated with last year's Gmail security breach may be attempting to gain access to our computers. There were a ...
3
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2answers
1k views

What directories/file permissions should i ensure are set?

I have a similar question about default software configuration. For this question i would like to ask What directories/file permissions should i ensure are set? Aprrently Is it normal to get ...
9
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1answer
483 views

Is locking the screen safe?

See USB driver bug exposed as "Linux plug&pwn", or this link Two choices [GNOME, Fedora 14]: Use the gnome-screensaver Use the "switch user" function [gnome menu -> log out -> switch user] ...
4
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2answers
3k views

How can I configure SELinux when the semanage command isn't found?

I'm having a very hard time configuring SELinux to allow Sending mail. Looking into selinux documentation I've found I can manage ports via the semanage command, but the command can't be found. Is ...
2
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1answer
2k views

Ideas for securing OpenVPN on an OpenWrt router

I put an OpenVPN server on port 1194 on an OpenWrt 10.03 router: echo "nameserver 8.8.8.8" > /etc/resolv.conf; opkg update; opkg install luci-app-openvpn openvpn openssl-util openssh-sftp-server ...
2
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1answer
3k views

How to connect to OpenVPN with NetworkManager

I have installed an OpenVPN server on my OpenWrt 10.03 router [freshly flashed]: https://pastebin.com/raw.php?i=hRECWuf1 echo "nameserver 8.8.8.8" > /etc/resolv.conf; opkg update; opkg install ...
0
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2answers
146 views

Where to handle packets between clients?

"Server": 192.168.1.1 I want to "theoretically" disable that the clients can "ping" each other. Can i use an iptables rule for it? e.g.: iptables -A FORWARD -m iprange --src-range ...
2
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1answer
245 views

tripwire report - inode number

Hi I am investigating tripwire and have stumbled upon something which i am unsure about. in a tripwire report generated after i modified hosts.deny to include an extra # I noticed the inode number ...
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1answer
1k views

IPTABLES rule for separating users

I have an OpenWrt 10.03 router [ IP: 192.168.1.1 ], and it has a DHCP server pool: 192.168.1.0/24 - clients are using it through wireless/wired connection. Ok! Here's the catch: I need to separate ...
89
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8answers
14k views

Which is the safest way to get root privileges: sudo, su or login?

I would like to have the root account in safety even if my unprivileged user is compromised. On Ubuntu you can only use sudo for "security reasons" by default. However I am not sure it is any safer ...
18
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3answers
2k views

Is it secure to leave a root shell running in detached screen session?

I'm curious about the security of leaving a root shell running inside a detached screen session. I typically never do this. Aside from the potential of my non-root user account being compromised ...
1
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1answer
130 views

Default configuration I need to change?

A few days ago I installed a new linux os. Today i realize /root has o+r (755) so EVERYONE is able to see my root sql password in /root/.my.cnf. I freaked out and simply changed /root to 750. My ...
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2answers
675 views

How can I disable /proc pseudo-filesystem on a shared Linux environment?

Is it possible to disable the /proc pseudo-filesystem to prevent w, ps, top, etc, from showing what other users are doing? Of course, I still want "everything else" to work correctly. Is there a ...
20
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3answers
906 views

Can other users view the arguments passed to a command?

If I invoke a command with arguments like so: bob@bob-pc:~$ command -arg1 -arg2 ...can other users view the arguments passed to the command?
3
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1answer
211 views

Is there a standard way to configure what policy iptables loads on startup under Debian?

I've just started playing with Debian 6.0 (Squeeze) in a VPS environment, as a way to learn more about system administration. One thing I'd like to configure is a default packet filtering policy. ...
7
votes
1answer
937 views

Why root's default shell is configured differently with other normal user account's default shell?

As I know, root's default shell is configured csh and normal user's default shell is sh in FreeBSD. And in Ubuntu, root is dash, normal user is bash. (refer: What's the Ubuntu's default shell?) Why ...
6
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2answers
4k views

Write to a file without redirection?

I am writing a regular compiled application that needs to create a special file and write a magic cookie into it. I can’t write the file directly from the application, the system security model ...
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1answer
178 views

What are the cons of posting dmidecode output publicly?

I remember somewhere mentioned that posting dmidecode output publicly is risky (security/privacy).
5
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3answers
213 views

I'm moving up from managed hosting to a VPS. What do I need to know?

I'll be starting to use a VPS for my web hosting this week, which is a big step-up for me since I've only used managed/shared services before. I've a bit of experience with Linux and I'm not afraid of ...
2
votes
1answer
1k views

How do you derive the passphrase from hexadecimal wep key?

I have a hexadecimal WEP key in the setting of my router. When I try to connect, the system asks me for the WEP passphrase. How can I derive it from my hexadecimal? This is what I have: ...
6
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1answer
3k views

What happens when your password expires and you're using key authentication?

on one of the boxes I don't control at work I use ssh keys to log in. Our passwords are set to expire after a few months. What happens if I don't reset my password and it expires? will I still be able ...
38
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4answers
5k views

Is there any way to keep a command from being added to your history?

Is there any way to keep a command from being added to your history? I have a command that I want to keep out of my history file, and I really don't care to have it there when I search the history ...
5
votes
3answers
499 views

Unix users, groups, and permissions

I don't understand unix users, groups, permissions, etc. For example, things managed by the chmod, chgrp, usermod, groupadd, etc. commands. How do all these things work?
6
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1answer
2k views

GNOME-keyring KWallet integration?

I use some GNOME apps, and some KDE apps, so some of them use G-keyring and some KWallet... What I would like to have is a single place for managing passwords. Is there a way to integrate G-keyring ...
4
votes
1answer
133 views

How can I run keychain in a way that only has the first shell prompt for keys on startup?

I open multiple shell tabs when I start KDE, and I've just added keychain to my ~/.shellrc the problem is that all the tabs prompt for key passwords when I login. This is quite annoying to do this. Is ...
7
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7answers
1k views

Is there a way to store Firefox passwords in a local encrypted database in Linux?

I want Firefox to "remember" my passwords so I don't have to type them in; unfortunately, the built-in password manager stores them in plain text, which is too high a security risk. I'd like to find a ...
14
votes
4answers
478 views

What specific vulnerabilities am I creating by disabling the sudo password?

Here are some instructions on how to disable your sudo password. These carry the following warning If you disable the sudo password for your account, you will seriously compromise the security of ...
9
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2answers
7k views

How do I get sudo -u $user to use the users env?

It seems when sudoing down that using sudo -u $user that the environment of root is still being used. How can I make sudo use the users environment? as a special note not all users that I will be ...
11
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5answers
981 views

Monitoring activity on my computer.

So recently I found that someone has been using my computer without consent, browsing folders, etc.... I could change all my passwords straight away, but I'm curious as the what the intruding party ...
1
vote
2answers
131 views

How would you create a user with the HOME_DIR field in /etc/passwd completely blank?

Closest I can come is: useradd --home / -r --shell /sbin/nologin someuser But this creates an entry into /etc/htpasswd that looks something like this: someuser:x:100:100::/:/sbin/nologin I want ...
14
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4answers
4k views

How to detect and remove a Linux trojan?

I recently (re)stumbled upon this: Linux Trojan Goes Unnoticed For Almost A Year (Unreal IRCd) Yes, I know that adding some random PPA/software from an untrusted source is asking for trouble (or ...
5
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3answers
2k views

How to clear terminal after logging out?

Currently on my laptop when I log out I can still see traces of my last activities (in tty). How can I tell it (Gentoo) to clear the screen before logging out?
3
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1answer
408 views

Are there any differences between mounting a /proc filesystem inside a chroot compared to mounting it from the outside?

Compare the following: mount -t proc none ./my_chroot/proc and: chroot ./mychroot mount -t proc none /proc
9
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2answers
1k views

What encryption does vim -x use?

I read man vim, :h -x and :h encryption none of this actually says what algorithm it's encrypted with.
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5answers
409 views

Does verifying packages enhance security and/or stability of a system?

RedHat/CentOS and Ubuntu both provide packages to verify the contents of a package. CentOS uses rpm -V. Ubuntu uses debsums. I've spoken to admins who run these tools to verify the packages on their ...