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It's not the Network! Ok, maybe it's the network...

Jason Rahm

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Top Stories by Jason Rahm

F5er and DevCentral community member ystephie is back with another great solution (check out her first solution here: BIG-IP APM Customized Logon Page), this time tackling brute force attacks utilizing customizations with the BIG-IP Access Policy Manager.  This solution requires BIG-IP 10.2.2 Hotfix 1 or later. Introduction Exposing applications or services to the Internet opens inherent security risks. BIG-IP Access Policy Manager (APM) provides edge authentication and access control services for applications, BIG-IP Edge Gateway provides secure SSL VPN services, and BIG-IP Application Security Manager (ASM) provides protection against a variety of attacks. In this series of APM deployment examples, we cover a couple techniques for protecting against brute force password-guessing attacks. In our first example (Part 1), we walked through the process of including a ... (more)

iRules IP Comparison Considerations with IP::addr Command

Anyone utilizing IP network comparisons in iRules is probably familiar with this syntax: 1: if { [IP::addr ]IP::client_addr[/24 equals 10.10.20.0] } { 2: ##Do this 3: } In fact, there are several methods for doing a comparison.  Here are three functional equivalents that include the most common form shown above: [IP::addr ]IP::remote_addr[/24 equals 10.10.20.0] [IP::addr ]IP::remote_addr[/255.255.255.0 equals 10.10.20.0] [IP::addr "]IP::remote_addr[ mask 255.255.255.0" equals 10.10.20.0] All three work, returning true if there is match and false if not.  These formats, however, a... (more)

Host that Sorry Page on your BIG-IP!

It's not an uncommon problem trying to figure out where to plant that sorry page in the event your farm is down.  It's also not an uncommon solution to just use your BIG-IP to issue a text-only HTTP::respond.  It works, but it's not, how do you say, visually appealing?  You want to say sorry and mean it.  With pictures.  If you take a stroll through the iRules codeshare, you'll notice several solutions to this problem.  All of them work, with a variety of methods, but user kirkbauer's entry takes it to another level.  Kirk's sorry page irule generator (written in perl) takes all ... (more)

Networking Options with LTM VE

Virtualization Expo on Ulitzer If you haven’t yet downloaded the  BIG-IP LTM VE trial, I highly suggest you do.  It is a fully-functional LTM, rate-limited to 1Mbps throughput.  If you’re not familiar with virtualized environments, hopefully this blog will fill in some blanks for how to get started on the network front. Getting Started Before downloading your VE image, you need to choose what virtualization environment you’re installing into.  The supported options in the type 1 hypervisor are VMWare ESX version 4 and ESXi version 4.  For the type 2 hypervisor (requiring a host O... (more)

Let iRules Work Around that ASP.NET Padding Oracle Attack

Microsoft released advisory 2416728 on Friday after researchers Thai Duong and Juliano Rizzo demonstrated the attack on ASP.NET with their Padding Oracle Exploit Tool.  The attack itself preys on a bug in ASP.NET’s AES implementation, which you can read about over here at threatpost.  So what’s the reward for a successful attack?  It’s not going to allow the attacker to execute code or elevate rights, but it does all the attacker to read potentially sensitive data that could then be further used to compromise the system. The mitigation for this attack is to obfuscate the server ... (more)