Security is not a product, but a process.

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22
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2answers
2k views

Why should I start to replace Windows Server 2003?

Windows Server 2003 is a very good operating system from Microsoft, and we're relying on it on a daily basis. I have heard that I should replace it by something "newer" and more "modern". Why should ...
22
votes
5answers
20k views

Does fail2ban do Windows?

Can anyone recommend a fail2ban-like tool for a Windows OS? I've got a couple of Windows Media servers that get hammered with brute force authentication attempts. I would like to plug these ...
22
votes
6answers
30k views

How do you avoid network conflict with VPN internal networks?

While there's a wide variety of private non-routable networks across 192.168/16 or even 10/8, sometimes in being thoughtful of potential conflict, it still occurs. For example, I set up an ...
21
votes
16answers
2k views

Why is it bad to have a weak mysql user password?

I was presented with an argument to the tune of "you don't need a strong mysql user password because in order to use it, they'd already have access to your server." We're talking about a 4 digit ...
21
votes
2answers
31k views

How to inspect remote SMTP server's TLS certificate?

We have an Exchange 2007 server running on Windows Server 2008. Our client uses another vendor's mail server. Their security policies require us to use enforced TLS. This was working fine until ...
21
votes
3answers
17k views

How secure is a bluetooth keyboard against password sniffing?

In a situation where an admin will enter sensitive information into a keyboard (the root password), what is the risk that a bluetooth keyboard (ship by default with Mac systems these days) would put ...
21
votes
10answers
4k views

How to track superuser activities

I'd like to know what are the best approaches for tracking superuser activities on a Linux environment. Specifically, I'm looking for these features: A) Logging keystrokes to a secured syslog ...
20
votes
8answers
3k views

How to prevent zero day attacks

Traditionally, all anti-virus programs and IPS systems work using signature-based techniques. However, this doesn't help much to prevent zero-day attacks. Therefore, what can be done to prevent zero-...
20
votes
8answers
19k views

Should I have to enable automatic update on Debian lenny stable?

I have installed a new Linux Debian lenny server that will be a LAMP and a Subversion server. Should I have to enable automatic updates? If I enable it, I am sure that I have the latest security ...
20
votes
3answers
37k views

How to check if a RSA public / private key pair matched

I have two files, id_rsa and id_rsa.pub, what command can be used to validate if they are the valid pair.
20
votes
3answers
3k views

how to secure an open PostgreSQL port

So, this is the situation. It seems we need to have an open TCP port 5432 to the world, where a customer has access to his PostgreSQL database. For obvious reasons, we can't say just "no", only as a ...
20
votes
3answers
15k views

Is the PHP option 'cgi.fix_pathinfo' really dangerous with Nginx + PHP-FPM?

There has been a lot of talking about a security issue relative to the cgi.fix_pathinfo PHP option used with Nginx (usually PHP-FPM, fast CGI). As a result, the default nginx configuration file used ...
20
votes
6answers
4k views

Is it okay to use a SSH key with an empty passphrase?

When I first learned how to make ssh keys, the tutorials I read all stated that a good passphrase should be chosen. But recently, when setting up a daemon process that needs to ssh to another machine, ...
20
votes
3answers
54k views

Network Service account accessing a folder share

I have a simple scenario. There's an application on ServerA that runs under the built-in Network Service account. It needs to read and write files on a folder share on ServerB. What permissions do ...
20
votes
3answers
31k views

How do I block specific IPs and IP ranges in IIS7?

I'm trying to block various IP addresses from every site that I have hosted from an server running Windows 2008 and IIS7. I've found various information about how to do this using Deny rules from "...
20
votes
2answers
1k views

Best Practices for updating a previously unmaintained server RHEL5.7

A new RedHat EL5.6 server has been recently put under my care. It is immediately obvious that, for the previous 12 months, little to no attention has been given to any sort of package updates. ...
19
votes
22answers
7k views

Why are Linux-based operating systems considered safer than Windows? [closed]

I hear that Linux-based systems are better for security. Apparently they don't have viruses and do not need antivirus software. Even my university claims this - they refuse to have Windows on their ...
19
votes
4answers
4k views

Ordinary users are able to read /etc/passwd, is this a security hole?

ls -l /etc/passwd gives $ ls -l /etc/passwd -rw-r--r-- 1 root root 1862 2011-06-15 21:59 /etc/passwd So an ordinary user can read the file. Is this a security hole?
19
votes
12answers
2k views

What language for starting on Linux? [closed]

I am about to begin a 4-year information security degree at Purdue. The degree does not call for any programming courses. So the only time I will be able to take one is the occasional elective. So ...
19
votes
6answers
5k views

Why would a university block incoming UDP traffic with destination port 53?

From my understanding DNS uses UDP and port 53. What undesirable things could happen if incoming UDP packets to port number 53 weren't blocked? UPDATE: Packets originate or are destined to the ...
19
votes
6answers
3k views

Bad to be logged in as admin all the time?

At the office where I work, three of the other members of the IT staff are logged into their computers all the time with accounts that are members of the domain administrators group. I have serious ...
19
votes
10answers
24k views

Live view of Linux shell commands executed by another user?

Is it possible for the root user in Linux to have a real-time (or close to real-time) view of the shell commands being run by another user logged in via a terminal or SSH? Obviously they're stored in ....
19
votes
5answers
38k views

How to check that an OpenVPN server is listening on a remote port without using OpenVPN client?

I need to check that an OpenVPN (UDP) server is up and accessible on a given host:port. I only have a plain Windows XP computer with no OpenVPN client (and no chance to install it) and no keys needed ...
19
votes
3answers
591 views

Suspicious .htaccess File

This was uploaded to one of my FTP folders. I'm not familiar with Apache, but still curious - can someone tell me what type of dastardly act this file is trying to commit? Thanks! RewriteEngine On ...
19
votes
7answers
19k views

Monitor an incoming SSH session in real time

Is there any linux software to monitor an incoming ssh session. At a previous job I was told that if you ever needed support from Red Hat for example you could have them SSH into your machine and you ...
19
votes
8answers
3k views

IT Audit checklist [closed]

I recently have taken on the position of a one man show for a company that is going to have an audit. The network isn't anywhere close to prepared and I have been looking for a general audit ...
19
votes
3answers
4k views

Securely wipe an entire Linux server with itself

I have remote ssh access and root access. I do not have physical access. I'm not looking for solutions involving booting into anything, I want to do this from what is currently running. OS is SL6. ...
18
votes
13answers
2k views

Reasons to not allow people into the server room

I have worked at a few hosting companies and seen two schools of thought on this Do not allow customers into the server room. The argument is basically it raises security (this news story is ...
18
votes
14answers
10k views

How can I destroy data on a failed hard disk without voiding warranty?

Suppose I have a hard disk with data I don't want to expose to a third party. The warranty period for that disk still lasts. Now the disk starts malfunctioning. I can't use a disk wiping program on a ...
18
votes
9answers
1k views

User password age/complexity policy

Has anyone got any resources for determining a reasonable password policy for my users? My personal leaning is to ratchet up password complexity and allow them to change them less often as a kind of ...
18
votes
13answers
2k views

Physical server security

A lot of time and columns are spent discussing securing a server from outside attacks. This is perfectly valid because it's easier for an attacker to use the Internet to break your server than it is ...
18
votes
3answers
70k views

What are the IUSR and IWAM accounts for in IIS?

I'm looking for a good explanation of the IUSR and IWAM accounts used by IIS to help me better configure our hosting environment: Why are they there? What's the difference between them? Do the names ...
18
votes
3answers
47k views

Iptables: How to allow only one ip through specific port?

How can I on my ubuntu server, in Iptables only allow one IP adress on a specific port? Thanks
18
votes
11answers
11k views

Are there any good reasons for disabling hardware-assisted virtualization?

We've had a number of servers from Dell recently, all of which have had hardware-assisted virtualization disabled in the BIOS. As far as I know hardware-assisted virtualization is a good thing - so ...
18
votes
8answers
8k views

Should we disable the root user?

Should we remove the root password, disable remote login and basically require adminstrators to use sudo to perform administrative actions?
18
votes
6answers
93k views

How to enable TLS 1.1 and 1.2 with OpenSSL and Apache

In light of a growing number of security issues, such as the newly announced Browser Exploit Against SSL/TLS (BEAST), I was curious how we could go about enabling TLS 1.1 and 1.2 with OpenSSL and ...
18
votes
2answers
3k views

nologin in /etc/shells is dangerous.. WHY?

I found this on the internet, while putting up a FTP server in FreeBSD. Putting nologin into /etc/shells potentially creates a back door by which those accounts can be used with FTP. (see: ...
18
votes
10answers
740 views

Should core system servers be able to connect to the internet for maintenance/support?

A couple of our servers have Oracle maintenance licenses. Our hardware vendor asked there was internet connection in the server room. Our policy is that all machines in that room is isolated from the ...
18
votes
3answers
50k views

Force authenticated user immediate logoff (emergency case)

In Active Directory if you want to prevent a user from logging in you can either disable their account or simply reset their password. However, if you have a user who is already logged in to a ...
18
votes
5answers
13k views

How can I chroot ssh connections?

I would like to setup a chroot jail for most (not all) users logging in though SSH. I've heard it's possible with the latest versions of openssh, but I've not been able to find out how to do it. The ...
18
votes
2answers
37k views

Troubleshooting Windows Authentication problems (no challenge) in IIS 7.5?

I know that there are thousands of reports of people having trouble getting Integrated Windows Authentication to work with IIS, but they all seem to lead to web pages that don't apply or solutions ...
17
votes
10answers
1k views

Is there a reason to upgrade Internet Explorer on Windows Server?

I never use Internet Explorer on my Windows Servers. Is there any reason I should upgrade Internet Explorer (version 6 or 7 to 7 or 8)?
17
votes
2answers
15k views

Is a central location for authorized_keys a good idea?

I'm in the process of configuring a cloud server to run the following stack: Ruby, Passenger, Apache; under Ubuntu 10.04 (Lucid Lynx). In the process of wanting to make the server easier to manage I ...
17
votes
6answers
22k views

Cygwin SSHd Autoblock Failed Logins

I'm running Cygwin with an SSH deamon on a Windows Server 2008 machine. I was looking at the Event Viewer and noticed as much as 5 to 6 failed login attempts per second (brute force) for the last week ...
17
votes
5answers
3k views

What are the “to-do” on protecting Windows server facing the web?

I currently begin to deploy Windows servers facing the web. And I would like to know what are you way of protecting your servers ? What softwares are you using ? On Linux, i'm using Fail2ban to ...
17
votes
9answers
2k views

Steps to take when technical staff leave

How do you handle the departure process when privileged or technical staff resign / get fired? Do you have a checklist of things to do to ensure the continuing operation / security of the company's ...
17
votes
7answers
4k views

Easiest way to send encrypted email?

To comply with Massachusetts's new personal information protection law, my company needs to (among other things) ensure that anytime personal information is sent via email, it's encrypted. What is the ...
17
votes
6answers
6k views

Updating production Ubuntu boxes the dos and don'ts

Every so often I login to production web/db/tools boxes and see the typical message: 30 packages can be updated. 16 updates are security updates. My question is, how do all of you handle updates on ...
17
votes
3answers
5k views

Automatically Applying Security Updates for AWS Elastic Beanstalk

I've been a fan of Heroku since it's earliest days. But I like the fact that AWS Elastic Beanstalk gives you more control over the characteristics of the instances. One thing I love about Heroku is ...
17
votes
2answers
17k views

User per virtual host in Nginx

Is it possible in nginx configure different user per virtual host? Something like server { user myprojectuser myprojectgroup; ... }