When I was a kid in 1975, my dad brought home a terminal with an accoustical coupler on the top where I could put a standard phone handset in, and communicate with a Microdata minicomputer at his work. [Dick Pick developed the operating system for the Microdata. To make it fast, he programmed it using […]
Netcat and Hammurabi
Using HfNetCk To Audit Windows Patches
There is a most fabulous utility available for free download from Shavlik Technologies here that will scan your Windows boxen for needed security/bug fixes. The command line version doesn’t require registration, and is quite easy to use. The cool thing is that the status of current patches is downloaded at run time. Let’s run this […]
Fizzer Worm is Nasty – Update Sigs, OK?
Yet another worm making the rounds via email. This one has a nasty payload. More info here. Removal tool here. Additional info for administrators and operators on IRC networks here.
Building a Security Audit Toolkit
As moon-howling, tree-hugging, packet-sniffing pagans, we like to celebrate the Summer Solstice by doing a security audit of the systems on our network. Spending the longest day of the year auditing systems will help us avoid spending the longest night of the year restoring a hacked one. In our audit, we will be disabling unused […]
Building a Chrooted sftp Environment
There was a time, not so very long ago, when we used to enjoy running an ftp server and locking our users into tiny little chrooted jails. While we still enjoy denying users their freedom, we now prefer to do so using a maximum security facility. The sftp file transfer program, which comes with OpenSSH […]
Running Nmap on Windows
We wrote about Nmap in this article, but this assumed that you were running Nmap on GNU/Linux. There is another version available, now, for Windows. We used nmapwin_1.3.0_src.zip on a Windows 2000 workstation. It is important to scan your network, especially when there is a lot of virus activity. Hopefully before, but we know how […]
Scanning Tool To Determine Unpatched Windows Boxes
Microsoft has published a tool available here that will tell you what hosts need patching to protect against the 823980 buffer overrun in RPC flaw (Blaster).
New Worm that Doesn’t Need Attachment
There is a new bagle worm that uses an exploit in IE. It does not need to have the user open an attachment, they just need to read an email with HTML in it. !!! There is a test to see if you are vulnerable here: http://secunia.com/MS03-032 More detailed info here: href=http://secunia.com/advisories/9580/ Bagle Q info […]
Verifying File Integrity with MD5 Checksums
We use MD5deep, because it has a recursive option which we discuss in this article. For now, though, we are just going to cover how to verify the MD5 checksum on a file. Grab the MD5 checksum from a site authoritative for your software package, and grab the software from a mirror site. Of course, […]
Using MD5deep To Verify Tree Integrity
We talked a little about MD5deep in this article. One nice thing about MD5deep is that it can do recursion. This allows you to create a set of MD5 sums for an entire directory. /etc is a good one to use as an example. Let’s create the set of MD5 sums: root@srv-1 etc # md5deep […]
Compiling PGP 2.6.2
This is certainly an old topic, but I always forget how to compile PGP 2.6.2 on GNU/Linux. Grab the source from MIT, probably, is what you want. You may also want to consider gpg. Much has changed since 1994! PGP 2.6.2 is particularly interesting for keeping password files using conventional encryption. It is possible to […]
Linux Kernel Exploit
There is a local user privilege exploit for the Linux kernel. Details are here: http://isec.pl/vulnerabilities/isec-0021-uselib.txt One thing to remember is that a local user does not mean that the user has to have access to the physical machine. It means that any user that can run code on the machine can gain root access.
Automating Secure FTP Downloads With Kermit
If you need to automate FTP downloads, and want lots of flexibility, an oldie but goodie is Kermit. I know what you’re thinking: “Hey, isn’t Kermit an old DOS comms program?”. Yes, it is a very old program. The cool thing about this, though, is that if you need to automate file transfers, it has […]
Configuring the Red Hat Enterprise Firewall
First off, let’s test ssh access: host user $ ssh x.y.z.w ssh: connect to host x.y.z.w port 22: Connection timed out host user $ Let’s add ssh access. Go to Applications->System Settings->Security Level: If you are not root, you will get a prompt to enter the root password: Be default nothing is enabled as trusted. […]
Running a Quick Ping Scan using NMAP
Nmap can make quick of work of doing a ping sweep of your network: [usr-1@srv-1 ~]$ nmap -sP 10.50.100.1-255 Starting nmap 3.70 ( http://www.insecure.org/nmap/ ) at 2005-06-13 15:50 PDT Host 10.50.100.1 appears to be up. Host 10.50.100.2 appears to be up. Host 10.50.100.22 appears to be up. Host mondo (10.50.100.72) appears to be up. Host […]
Securing PHP
The first step to secure PHP is from the system perspective. Only provide what you have to. Of course, the code needs to be secure as well by using proper input validation, encryption, etc., but as systems administrators, we can head off some problems. First off, you can view a complete rundown of your current […]
Setting Up a Windows Server 2003 Host Based Firewall
There is a false sense of security when you envision your network as inside and outside, with a firewall protecting you from hostile users on the outside. One particularly nasty problem is when users bring their laptops home, surf, read email, and then plug it right back in to the corporate LAN on Monday morning. […]
Spike in Port 12345 Traffic
We have noticed a surge in traffic on port 12345. This could be NetBus, or a variant. We suspect that some trojan backdoor is in the wild tacked on to a new worm. The worm is looking for other friendly hosts listening on port 12345. To see a historical chart of activity on this port, […]
Using the AFICK File Integrity Checker
One important component of securing a system is to use a file integrity checker.There are multiple tools out there that can do this, including AIDE, and Tripwire. One project that does what we need, has few installation requirements, is fairly easy to install, and is multi platform is AFICK. In this article we will install […]
Customizing the AFICK File Integrity Checker
In this article, we set up AFICK. Let’s adapt AFICK to use a particular directory tree and a different database. This way, we can fingerprint the OS on one run, and fingerprint more dynamic content with a different job. Here is our configuration file: [root@ids afick]# cat /etc/afickweb.conf database:=/var/lib/afickweb/afick history := /var/lib/afickweb/history archive := /var/lib/afickweb/archive […]
