Security is not a product, but a process.

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Why is /dev/urandom only readable by root since Ubuntu 12.04 and how can I “fix” it?

I used to work with Ubuntu 10.04 templates on a lot of servers. Since changing to 12.04 I have problems that I've now isolated. The /dev/urandom device is only accessible to root. This caused SSL ...
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6answers
1k views

How to choose a cloud service for backups

I am thinking of using a cloud service to backup one of my client's website. My (clients) main concerns are (in decreasing order of importance) Protection of IP (trade secrets, source code), user ...
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2answers
2k views

How did spammer spoof emails with my google apps domain (it even has DKIM!)

I have been getting a lot of bounce-backs lately. I thought my google apps account has been compromised, but there is no activity on my apps account, and there is certainly no malicious user that I ...
10
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3answers
637 views

Cisco ASA and multiple VLANs

I currently manage 6 Cisco ASA devices (2 pairs of 5510s and 1 pair of 5550s). They all work quite nicely and are stable so this is more of a best-practice advice question rather then "OMG it's ...
10
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1answer
635 views

How do I audit user's mailbox actions performed via IMAP in Exchange 2010?

I read through the Technet article on Mailbox auditing but it seems to only be working for MAPI access. I perform the following cmdlet to enable auditing of the owner: > Set-Mailbox -Identity ...
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7answers
7k views

How to disable responses to PING [on hold]

I feel like this should be a really simple thing to do, but googling and checking SF I didn't see anything. I'm trying to make my Fedora server not respond to pings, how do I do that?
9
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12answers
724 views

When I have to administrate an existing Linux server what's the best way to check if it is secure?

There are many tutorials on how to set up a new secured server. But what if I have to administrate a server someone else had set up some time ago and I don't know much about its configuration yet? ...
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5answers
32k views

SSH / SSHD - How do I set max login attempts?

What is the easiest way to setup max login attempts in a LAMP environment (sshd installed via yum)? Is there a package or simple firewall rule?
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8answers
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How to secure phpmyadmin?

I checked out my apache logs, and, whooooaaa, there are a lot of bots trying to exploit phpmyadmin. The first thing i did was to change the directory name to something more obscure. But, are there ...
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3answers
21k views

Allow linux root user mysql root access without password

On cPanel when I am logged in as root and type "mysql" without hostname and password it gives me direct access to mysql root user. I would like to do this for one of my non-cpanel server where the ...
9
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6answers
516 views

Security Admins toolkit? What's in yours? [closed]

Resource question :- I need to collate a list of security admin tools For: Web Network Wifi Server unix/Linux/windows/macosx SQL Xss Please state -links/version/os used/free v buy
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15answers
4k views

How to manage rack keys?

As a result of a security audit there's the need to lock the racks and manage the keys: Keep the keys safe Record key usage Complying with these two requirements has many challenges as there are a ...
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10answers
13k views

Relatively easy way to block all traffic from a specific country?

I have a web app that has no users in the Philippines, but is constantly bombarded by spammers, carders testing cards, and other undesirable activity from there. I can see in the logs that they have ...
9
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3answers
6k views

Is there danger to virtualizing a router?

I had read on a few forums about pfSense that said it was dangerous to virtualize pfSense. The reason that was stated was an attacker could use pfsense as a spring board for an attack on the ...
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3answers
5k views

What is HTTP COOK request method in my logs?

I'm seeing entries in my Apache logs like the following 178.216.185.210 - - [24/Feb/2014:11:46:40 -0500] "COOK /freesearch.php?portal=0a9&... HTTP/1.0" 303 589 "-" "Mozilla/4.0 (compatible; ...
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3answers
515 views

Why does a web server's public key certificate have to be signed by a certificate authority?

In other words, what would be the security risk of not signing public key certificates by certificate authorites (from a user perspective)? I mean, the data is still encrypted... What could a man in ...
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4answers
2k views

When is it appropriate / prudent to use chroot?

I hear about needing to chroot BIND all the time. Fair enough. But what about other programs? What are the "rules" (either personal or widely accepted/established) for deciding which programs ...
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8answers
18k views

How to prevent a LOIC (DDOS) attack? [duplicate]

The program LOIC (in the news a lot the last days) causes a lot of damage. What can I do on my server to prevent this kind of attacks? Auto-block ip when receive a strange connection? Because mostly ...
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2answers
4k views

Is SSH Key Exchange more secure than password authentication?

Remote users connect to several services at our main office over the internet using SSH. The SSH password is synchronized with their LAN A/D account. Would having users bring a copy of an SSH key ...
9
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2answers
4k views

Is it possible to have a 100% secure virtual private server?

I am curious if it is possible to have a VPS that has data on it that is not readable by the hosting provider, but is still usable on the VPS. Obviously there are some things that you could do to ...
9
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3answers
346 views

“Template” for handing out user & passwords for employees

Within this relatively small company I work for, I have been handing out usernames and passwords written very simply in a word document. I wish for this process to be more professional now that we ...
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4answers
50k views

How can I know when a file was last read or accessed on Windows?

I need to determine if a particular file was accessed in the last, say, 2 days. Is this possible on Windows Server 2008 R2?
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6answers
714 views

DDoS. Are we that helpless? [duplicate]

With recent DDoS incidents related to wikileaks, I can't help but feel that pretty much all sites online are very vulnerable to such attacks. Visa, MasterCard (to name a few) have shut down because of ...
9
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2answers
315 views

Method to deprecate SSH key Pair locally

I've using my ssh-keys for a while. I'm thinking about to upgrade my ssh key pair to a stronger encryption and i dont know all devices where my keys are registered. Is it posible to "deprecate" a SSH ...
9
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1answer
17k views

Disable SSL / TLS compression in Apache 2.2.x

Is there a way to disable SSL/TLS Compression in Apache 2.2.x when using mod_ssl? If not, what are people doing to mitigate the effects of CRIME/BEAST in older browsers? Related Links: ...
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6answers
971 views

When/why to use a web proxy/gateway?

Right now we have about a 25-30 PC network, connected to the internet with a run-of-the-mill SonicWall Firewall/Router device. There isn't much filtering / blocking other than outgoing SMTP (for ...
9
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1answer
780 views

Is it possible to hide a malicious alias in Bash on Linux?

Is it possible to conceal the existence of a malicious alias in Bash on a Linux system and have it executed by the user without their knowledge?
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2answers
22k views

HOWTO: Disable complex password policy on Hyper-V Server 2008?

How do you disable the password complexity requirements on a Microsoft Hyper-V Server 2008 R2? Keep in mind that when you log into the server, the only UI you have is: And you cannot run ...
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6answers
6k views

How can I log users' bash commands?

I'm running a debian etch server where users will be logging into (hopefully) a chroot jail through ssh. How can I have the commands they execute logged in a way they cannot delete, nor prevent?
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4answers
6k views

Is there a difference between a self-signed certificate and one signed by your own CA?

We need to use SSL on our internal network for a few sensitive applications, and I need to know if there is a difference between a self signed certificate and one signed by a Windows Server CA that we ...
9
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4answers
7k views

How do you manage service account credentials (passwords)? [closed]

In a Windows environment how do you address the following issues with service accounts? Regular Password changes - with single service accounts used on multiple machines how do you regularly change ...
9
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3answers
1k views

Real life SELinux security example?

Can anyone give a real life example of where SELinux saved their security bacon? (or AppArmour if you wish). If not your own, a pointer to someone with a credible experience? Not a lab test, not a ...
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2answers
28k views

Filtering Security Logs by User and Logon Type

I have been asked to find out when a user has logged on to the system in the last week. Now the audit logs in Windows should contain all the info I need. I think if I search for Event ID 4624 (Logon ...
9
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1answer
6k views

How to install multiple Intermediate CA Certificate files on Apache?

I just bought a SSL certificate, and here are all the certificate files i got: Root CA Certificate - xxCARoot.crt Intermediate CA Certificate - x1.crt Intermediate CA Certificate - x2.crt ...
9
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1answer
195 views

Can I reasonably use SHA-256 in a DNSSEC deployment?

I know that RFC 5702 documents the use of SHA-2 in DNSSEC, and that RFC 6944 defines RSA/SHA-256 as "recommended to implement." What I'm not aware of is just how widely-implemented SHA-256 is in ...
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2answers
3k views

When should I create a new user account to run software on a server?

In general, when should one create a new user account to run a piece of internet-facing software on a server? For instance, suppose I'm using a shared Debian server (e.g. via Dreamhost) and I want to ...
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3answers
2k views

Should I create a new private ssh key on each system?

I need to connect to multiple servers from multiple devices via SSH. I'm wondering if I should be creating a new id_dsa file on each device I'm connecting from, or if there isn't a problem copying the ...
9
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2answers
513 views

Managing IAM security credentials for multiple docker containers

Within plain EC2 environment, managing access to other AWS resources is fairly straightforward with IAM roles and credentials (automatically fetched from instance metadata). Even easier with ...
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3answers
6k views

Applocker vs Software restriction policy

The goal is to prevent users from running unwanted programs on a terminal server. I have read many articles from Microsoft and others saying that the new Applocker feature is 100% better than the ...
9
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1answer
252 views

Where can I embed proprietary information in a layer 2 or layer 3 packet?

The Citrix Netscaler has an interesting property that embeds information in the TCP packet that gets sent to the host. This property is echoed back to the Netscaler in such a way that the Netscaler ...
9
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1answer
1k views

Configuring WPA2-Enterprise with Freeradius

I'm trying to set up an authenticated wifi network with Freeradius. I've managed to get things working using self-signed certs etc. The problem is Windows clients need to uncheck the "Automatically ...
8
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13answers
2k views

Locking Desktop USB Ports

How do you lock out the USB ports on the desktop PCs so we can prevent usage of USB drives on the desktops. I should clarify that these are Windows XP desktops. We should also assume that like most ...
8
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9answers
5k views

What should I do about someone trying to brute force attempt to login to our SQL Server 'sa' account?

Looks like someone or something is trying a brute force attempt at logging into our production SQL Server instance with the 'sa' account. They haven't been successful because our 'sa' account is ...
8
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6answers
616 views

First time opening an SSH server to internet, what to check

I've been running a few servers for a relatively long time, but I always only rented them, so I don't have much experience securing the actual server (as opposed to the application I'm running on it). ...
8
votes
13answers
7k views

How do I stop Ubuntu from starting daemons I've not explicitly asked to run?

One of the basic principles of computer security is never to run anything you don't need. I was pgrepping for a process today when I noticed that my Ubuntu 9.04 (desktop) machine was running a git ...
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5answers
3k views

Pain removing a perl rootkit

So, we host a geoservice webserver thing at the office. Someone apparently broke into this box (probably via ftp or ssh), and put some kind of irc-managed rootkit thing. Now I'm trying to clean the ...
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7answers
6k views

Is there anyway to determine who dropped a table?

A table in the production database has 'mysteriously' disappeared. Does anybody know of any way to diagnose what the heck happened to it? And who did it? Edit 1: This is an internal app, with weak ...
8
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2answers
1k views

How to configure iptables so an unwanted port is not reported as filtered

I'd like to stop others from seeing my ports as filtered in the nmap standard scan (unprivileged). Let's say that I have the following ports open: 22, 3306, 995 and a firewall configured like this: ...
8
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4answers
714 views

How can I fake port 22 when I made sshd listen to another port?

Instead of making the possible hackers from port scanning my server I would like to just fake that sshd is listening on port 22 and log the attempts. Will it make sense doing that? If yes, what ...
8
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3answers
655 views

What are some best practices when taking over IT at a new company? [closed]

I thought this would make for a good topic with some interesting suggestions. What are the first things you would do when taking over IT at a new organization? What are some red flags you would look ...