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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1answer
147 views

knock on Scientific Linux 6.1? (perl script for knocking?)

I have an OpenWrt router where I installed knockd: knockd.conf [options] logfile = /var/log/knockd.log [openSSH] sequence = 7000,8000,9000 seq_timeout = 5 command = ...
7
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1answer
258 views

Why is it a security problem to have /usr/sbin owned by bin?

The Sendmail Installation and Operation Guide (§1.3.1) asserts: For security reasons, /, /usr, and /usr/sbin should be owned by root, mode 07552[...] 2Some vendors ship them owned by bin; this ...
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3answers
684 views

Is encrypting your web browsing via SSH to localhost useful?

For example, if I did an ssh -X to localhost and invoked Firefox, would that be enough to be considered safe browsing, like if done on some public wifi?
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2answers
2k views

Why is mount.cifs not installed suid by default?

I am using Gentoo, and on my machine at least mount.cifs is not installed suid root by default. In particular, this means that I can't use the user mount option with CIFS shares. I noticed that ...
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2answers
1k views

Preventing access to TTY when X is killed

Assume I start an X server manually from a virtual console /dev/tty1 with xinit or startx, with the line id:3:initdefault: set in /etc/inittab. The X server gets run and put on another virtual ...
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2answers
1k views

fprintd-enroll works with right-index finger only

When I try any other finger with: %> fprintd-enroll left-index-finger Using device /net/reactivated/Fprint/Device/0 failed to claim device: Not Authorized: ...
3
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1answer
91 views

Encryption of home directory for securing data after harddisk corruption

Always when I install Linux OS (e.g. Ubuntu), there is a possibility to encrypt the home directory. I was asking myself why is this useful. Is it good in the case when my harddrive is corrupted and I ...
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2answers
832 views

Can someone change content of a file with permission 777 on a server?

If in my server I have a file(for example a php file) with permission 777, can someone edit or delete it without having an account on the server?
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1answer
1k views

What is the default encryption type of the ssh-keygen?

When generating private/public keys with ssh-keygen what types of keys will it generate if I wont pass -t option followed with the encryption type like rsa?
4
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1answer
499 views

Why do SELinux policies require a system restart?

When changing SELinux policies, I've been reading that you're required to restart the system. What changes would require this? Are there certain policy changes that would not require a restart?
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3answers
883 views

Is there a good way to encrypt and store a mailbox while still being able to quickly access and search it?

I am wondering if it is possible to : Store a mailbox in a way that the system administrator (ie: root) cannot see it User(s) with the valid credentials would be able to see it AND be able to search ...
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4answers
56k views

SSH login with clear text password as a parameter?

I need to login to a user that I've created on a remote host running Ubuntu. I can't use an ssh key because the ssh login will happen from a bash script ran within a server that I wont have access to ...
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1answer
2k views

See if file has been copied to USB

Is there a way to see if a file has been copied to an USB drive? (Ex: I have the file secret.db and I suppose that my friend has copied it into his USB drive. With stat $filename I cannot see the ...
3
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1answer
491 views

How to check downloaded package on OpenBSD 5.1?

Under linux there is a package called "ubuntu-keyring" - it's for checking that the downloaded packages (from the offical repositories) are the ones that are on the server. How can I do this under ...
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5answers
19k views

vsftpd fails pam authentication

Moving a tried-and-true vsftpd configuration onto a new server with Fedora 16, I ran into a problem. All seems to go as it should, but user authentication fails. I cannot find any entry in any log ...
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2answers
3k views

Should you run automatic updates

I'm running production Centos web servers. I want to know what is best practice for running updates. Should I automate this with yum-cron or yum-updatesd? Or is there a danger of updates breaking ...
4
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2answers
931 views

How to set secure permissions for multiple users and multiple websites?

On a Gentoo 3.2.12 server with apache2+php, there are several websites running: /www /website1 /website2 ...etc The apache user should have read-only access to all the websites. There ...
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2answers
309 views

Linux security vulnerabilities?

A while back I started an embedded project using the 3.2.10 kernel. Now the project should go into production and the stable kernel is 3.2.16. I would prefer not to upgrade anything to avoid ...
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3answers
6k views

Fork bomb on a Mac?

I just learned about a fork bomb, an interesting type of a denial of service attack. Wikipedia (and a few other places) suggest using :(){ :|:& };: on UNIX machines to fork the process an infine ...
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0answers
283 views

Information about the 1630/master app

When I run $ sudo netstat -a --programs | grep LISTENING | grep 1630 I will get this output. Do you know what good are processes running under this app name? Why they I running on my system and if ...
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3answers
262 views

How can I identify processes that use network facilities, and can they be killed?

In the output of netstat -a | grep LISTEN there are usually a lot of processes. How (where) can I find out information about them, what is their purpose in the system and if I can kill them? Which ...
10
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2answers
682 views

How do I prevent programs from sniffing keystrokes to su/gksu?

I've read here that it's possible for any app using the X server to sniff keystrokes to any other app which is also using the X server, including su (on a terminal) or gksu. I've heard of a few ways ...
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1answer
414 views

How to know who accessed a file or if a file has 'access' monitor in linux

I'm a noob and have some questions about viewing who accessed a file. I found there are ways to see if a file was accessed (not modified/changed) through audit subsystem and inotify. However, from ...
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4answers
164 views

Erasing HDD , re-write only headers , is that safe?

I want to erase my HDD quickly with dd, so If I only "zeroify" the partition headers , like destroy the inode table, block size etc. But is that safe? UPDATE I have some partition not encrypted ...
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2answers
646 views

Is xinetd still the best method to let non root daemons listen on privileged ports?

When I need to use SNMP monitoring for java applications, there is the need to that application (usually ran as daemon user) to listen on snmp port. If there is no other alternative, of course I can ...
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2answers
1k views

Arch: Is “SigLevel = Never” the only convenient way?

The only way I can install majority of packages without rejection from signature database is to put SigLevel = Never in pacman.conf. Its not supposed to be the right way, but I don't seem to be able ...
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1answer
120 views

A tool that helps me to be sensible on permissions?

Is there a tool or understandable source (manual, webpage, ...) in existence that helps a moderate* user to be more sensible about user permissions? In my ideal-dream-world I'd have a CLI tool that ...
2
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1answer
271 views

dm-crypt and LUKS password rotation

How do you protect the master key, and distribute multiple passwords for admin access? Is there a 3rd party user management tool or is this native?
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1answer
438 views

How do I hide login information passed to command line programs from appearing in the process list?

I have to execute a program that passes in as command line options the username and password. Is there a way to hide the username & password from appearing in the /proc entry for this process.
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3answers
2k views

Is it safe to close shell just by clicking “X” or using “ctrl+d”?

Is it safe to close shell just by clicking "X" or using "ctrl+d" while logged in as root with su or is it safer to close it by typing "exit"? Is there any difference (security-wise) at all or is it ...
3
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1answer
192 views

How are loaded SSH keys referenced by name?

I'm using chef's knife ec2 tool which requires the name of a loaded SSH key (that was created in the Amazon EC2 control panel) It seems strange to me that it uses a name to reference the keypair - ...
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1answer
257 views

Hamachi for Web Surfing

I recently installed Hamachi on my FreeBSD 9 and I want to know how can I browse web anonymously by this software?
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2answers
98 views

In Gnome, how do I decide whether to accept a PackageKit software source?

When I try to install software in the Gnome environment of Linux (mine is openSUSE) from a repository that I have not used before, PackageKit asks me to respond "Yes" or "Cancel" to a dialog "Software ...
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4answers
253 views

Steps to secure your server? [duplicate]

Possible Duplicate: What to use to harden Linux box? Apparmor, SELinux, grsecurity, SMACK, chroot? I'm just completed install my web server. So what should i do to secure it? I just ...
6
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1answer
994 views

Jailbreaking HDTV

I have a Vizio internet TV, the predecessor to this one with basically the same specs, not 3D though. I wanted to try and gain root access to the tv. Using nmap I leaned that the only port open is ...
3
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2answers
242 views

SSH Bash Jail Session

I've seen some game tunneling service providers that jails the customer's account to a Information screen upon login and any input is ignored. Ctrl+C closes the SSH session, and disconnecting. This ...
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2answers
1k views

Allow non-root process to access all home directories without compromising security?

Any ideas how to allow one non-root process to access (read&write) all home directories without compromising security? Normal users should not have access to each other's home directories. All ...
11
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3answers
13k views

How can I block a range of IP addresses with an Amazon EC2 instance?

I know a certain range of IP addresses are causing problem with my server, 172.64.*.* what is the best way to block access to my Amazon EC2 instance? Is there a way to do this using security groups or ...
3
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1answer
138 views

What is the best way to restraint/secure a workstation?

I want to prevent users to copy on usb devices and some others actions. I was thinking of using polkit. Do you think it is a good solution or does someone know some alternatives ? EDIT: I also need ...
8
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1answer
3k views

Linux: LUKS and multiple hard drives

I have a Debian Linux system (amd64) installed on a RAID-1 system encrypted device (LVM on LUKS) and will have a RAID-6 of >=4 disks where I'll put my data (LUKS and maybe LVM). I think the basic ...
2
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0answers
119 views

Why do I get a different RSA fingerprint when multihopping using ProxyCommand

I'm using the following config to connect to multihop to the target host (gw2 and target have my public key stored in the authorized_keys file ; no netcat on all systems): Host gw1 HostName ...
2
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1answer
307 views

Securely Deleting A File In Ram

I'm running a live distro in ram. I need to write a password to a file. Later, I need to delete it securely. I don't know how live file systems work, so I'm unsure if I open the file for writing, ...
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5answers
1k views

Securing a Debian installation for general home usage

Debian comes with several harden packages, designed to make a computer more secure. My needs are very simple: word processing and Web browsing. I do not run any special servers, do not use SSH, ...
3
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1answer
948 views

Disabling Web camera

My Eee PC comes with a Web cam, which I never use. How can I ensure that it is effectively disabled, so that no software can use it?
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1answer
825 views

Any better alternative to chroot on an OpenVZ VPS?

Are there any better alternative to chroot environment? I'm thinking about running nginx on a jailed environment. BTW, I'm on OpenVZ VPS, so modifying the Kernel is a no-no. (I think that prevents ...
10
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1answer
642 views

Why aren't the Fedora GPG keys signed?

Fedora uses GPG-keys for signing RPM packages and ISO checksum files. They list the keys in use (including fingerprints) on a web page. The web page is delivered via https. For example the checksum ...
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2answers
678 views

Why did SDF switch from NetBSD to Linux?

I personally don't have much experience, but I was reading about SDF, and at one point the article mentions that SDF migrated to Linux in 1997, but due to the large number of malicious attacks it ...
2
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1answer
598 views

SELinux outbound access to other sites with restrictions

We have CentOS 6 configured with SELinux to host a number of websites. Unfortunately SELinux is preventing websites from accessing (outbound) sites, such as download.wordpress.com to update ...
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3answers
2k views

Can SSH passwords be sniffed out over Wi-Fi?

When you ssh, can the password you enter to connect, be intercepted if you're using untrusted public Wi-Fi (coffee shop, library, airport, etc).
3
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1answer
433 views

Does using epub2pdf pose a potential security risk? Is there an alternative?

epub2pdf is a fairly platform-independent program. Based on Java, it executes without a hitch on my machine, with no dependencies. However, strangely enough, the program requires an active internet ...