When huge mass of PCs are affected by a network worm in a large corporation, some percentage of them belongs to traveling personnel so disinfection is difficult.
Infection is accomplished via Microsoft RPC overflow on pert 137, so we can do little to prevent it (other then enabling automatic patch downloads on desktops, which is not a NTI/R domain, anyway). The start of payload is
length = 50
000 : 80 B0 00 00 00 01 00 00 00 00 00 00 20 43 4B 41 ............ CKA
010 : 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 AAAAAAAAAAAAAAAA
020 : 41 41 41 41 41 41 41 41 41 41 41 41 41 00 00 21 AAAAAAAAAAAAA..!
030 : 00 01
If the worm body is transfered from PC to Pc via TFTP an effective measure is to blocking TFTP on site routers for DHCP segments only (TFTP traffic "to" DHCP segments should be allowed as to measure who else is affected by the worm). Doing it one site a time and proceeding slowly so that the whole change took enough time for us to understand consequences. VPN are very important source of infection here and probably the candidate No.1 for such measure.
Anyway, finding and blocking important for fiunctioning of network worm parts on site routers is a very effective and relative gageneral strategy. It definitly helps to prevent infection of servers from desktops and thus negative effect on the unpatched Windows servers (automatic updates are rarely enabled on servers, and that's probably for a reason).
This is not limited to worms which use TFTP as transport mechanism.
Google matched content
The Trivial File Transfer Protocol (tftp) is used most often for updating firmware in routers and in some boot from network environments, most often in the Unix world. Additionally, some IP Telephony vendors are using it to load boot images for their phones.
Unfortunately, most vendors provide a userland, interactive tftp server piece, which requires an actively logged in user to run - which is a security risk. The few commercial packages that support tftp aren't free.
Fortunately, Microsoft includes a free one, but doesn't have any information on setting it up or configuring it. ... However, I came across a Reader-to-Reader suggestion from Windows 2000 Magazine (http://www.win2000mag.com) that included instructions for installing and configuring the tftpd.exe daemon which is shipped with Windows 2000 Server. The following instructions are from the article, which is available in its entirety here. http://www.win2000mag.net/Articles/Index.cfm?ArticleID=26648
Copy the tftpd.exe file from \%systemroot%\system32\dllcache to \%systemroot%\system32.
Then, use the Microsoft Windows 2000 Server Resource Kit's Instsrv utility to create the service as follows.
instsrv tftpd c:\winnt\system32\tftpd.exe
To start the service, enter
net start tftpd
You have now created a TFTPD server on Win2K. To test the server, enter
tftp -i put <filename>
The service will create a directory named tftpdroot in \%SystemDrive%, and the file whose name you entered above will be in this directory. This is where the first issue arose. We already had an existing data directory that needed to be available via tftp, and we do not serve any content off the system drives of any servers – it is both a security and common sense issue. Therefore, the service needed to be configurable.
Because this isn’t a supported service, finding documentation on it wasn’t going to be easy, and after a few minutes with Google, I determined I’d have to create my own documentation. Since it only makes sense that a Microsoft application would look to the registry for configuration data, I grabbed my copy of RegMon, the free registry monitor from Systernals, and got busy.
After tweaking RegMon’s filter to only show the tftpd.exe process, and setting a highlight on the service’s registry key (HKLM\CurrentControlSet\Services\TFTPD), I started the service. Looking through the dozen or so highlighted registry accesses revealed the start of something good – an OpenKey attempt for this key:
A quick glance in RegEdt32 showed that key didn’t exist, so let’s add it. Many Windows services have a Parameters key, so this is a good sign.
After adding the key, a stop and restart of tftpd shows a sequence of QueryValue commands – attempts to read a set of values. The values it is looking for were:
BINGO! The first parameter tftpd is looking for is called directory. Let’s add a value of type REG_SZ with the value data set to “D:\tftpdata” (our tftp data directory). Following a restart of the tftpd service, we’ll retest (as described above) and we got it – the service now points to our data directory, and the file we just uploaded. Unfortunately, none of the other values are documented either, so they are probably best left alone.
The Windows 2000 Standalone TFTP Daemon
The Trivial File Transfer Protocol (TFTP) services is used widely on TCP/IP networks today. Examples of usage are; firmware updates for switches and routers, remote booting and the Remote installation Service in Windows 2000/Server 2003.
Windows 2000/Server 2003 features a TFTP service as part of the Remote Installation Service. There is no way to install the TFTP Daemon, as it is called, without installing RIS as well. Installing RIS means adding at least one Windows Pro image to your server and running the SIS Growler and the BINL services as well. You can elect not to configure RIS, but then you get constant errors in your event logs about the RIS subsystem not being configured.
I have created a stand alone version of the Microsoft TFTP Service which you can download here. I can be run on all Windows 2000 or later operating systems. Needless to say you have to have a license for Windows 2000 Server to use this service. Even if you run it on Windows 2000 Professional.
The current version of the package is 1.1.
Download it here: TFTPDaemon_v1.1.zip
Filename Info Author tftpd.exe The executable file that runs the TFTP service. This file is copied from a Windows 2000 Server with SP3. (When SP4 come out I will replace this file with the newer version.) Microsoft Corp. InstallTFPTDaemon_vX.X.vbs Installation script for the service. MDS RemoveTFTPService_vX.X.vbs Uninstaller for the service. MDS TFTPAdmin_vX.X.vbs Admin script to change the TFTP Root directory. MDS
- The service has no logging or user interface. Errors, if any, are reported to the Event Logs.
- The service supports the "tsize" option, which is required for PXE boot.
- Upgrading firmware on switches, routers, terminals.
- PXE boot (TFTP Daemon is tested with Thinstation and works flawlessly).
- Distributing files without requiring usernames or passwords.
- Extract the files in the archive to a folder of you choice.
- Run InstallTFPTDaemon.vbs.
You will be prompted for the TFTP Root directory; the folder must exist before you select it. The script will not create it, but it will check if the folder exists. Then tftp.exe will be copied to your %systemroot%\system32 directory, the service will be installed in the registry and the service started. You will be prompted with info whether the service was installed successfully or not.
If you need to change the TFTP Root directory you use the TFTPAdmin script. It will read the current TFTP root directory and prompt you for a new one, and the restart the service. There is no checking of what you enter in the new folder field (I haven't programmed it yet). Be careful to enter an existing directory.
If you whish to remove the TFTP service you can run RemoveTFTService. It will stop the service, unregister the service from registry and delete the tftpd.exe file. You will be prompted with status of the operation.
- Extract the TFTP service from Windows Server 2003 (If it is improved).
- Improve script with more error checking (when I get more time).
Support or info is me and you can reach me at mds(at)tiscali.no
Groupthink : Two Party System as Polyarchy : Corruption of Regulators : Bureaucracies : Understanding Micromanagers and Control Freaks : Toxic Managers : Harvard Mafia : Diplomatic Communication : Surviving a Bad Performance Review : Insufficient Retirement Funds as Immanent Problem of Neoliberal Regime : PseudoScience : Who Rules America : Neoliberalism : The Iron Law of Oligarchy : Libertarian Philosophy
War and Peace : Skeptical Finance : John Kenneth Galbraith :Talleyrand : Oscar Wilde : Otto Von Bismarck : Keynes : George Carlin : Skeptics : Propaganda : SE quotes : Language Design and Programming Quotes : Random IT-related quotes : Somerset Maugham : Marcus Aurelius : Kurt Vonnegut : Eric Hoffer : Winston Churchill : Napoleon Bonaparte : Ambrose Bierce : Bernard Shaw : Mark Twain Quotes
Vol 25, No.12 (December, 2013) Rational Fools vs. Efficient Crooks The efficient markets hypothesis : Political Skeptic Bulletin, 2013 : Unemployment Bulletin, 2010 : Vol 23, No.10 (October, 2011) An observation about corporate security departments : Slightly Skeptical Euromaydan Chronicles, June 2014 : Greenspan legacy bulletin, 2008 : Vol 25, No.10 (October, 2013) Cryptolocker Trojan (Win32/Crilock.A) : Vol 25, No.08 (August, 2013) Cloud providers as intelligence collection hubs : Financial Humor Bulletin, 2010 : Inequality Bulletin, 2009 : Financial Humor Bulletin, 2008 : Copyleft Problems Bulletin, 2004 : Financial Humor Bulletin, 2011 : Energy Bulletin, 2010 : Malware Protection Bulletin, 2010 : Vol 26, No.1 (January, 2013) Object-Oriented Cult : Political Skeptic Bulletin, 2011 : Vol 23, No.11 (November, 2011) Softpanorama classification of sysadmin horror stories : Vol 25, No.05 (May, 2013) Corporate bullshit as a communication method : Vol 25, No.06 (June, 2013) A Note on the Relationship of Brooks Law and Conway Law
Fifty glorious years (1950-2000): the triumph of the US computer engineering : Donald Knuth : TAoCP and its Influence of Computer Science : Richard Stallman : Linus Torvalds : Larry Wall : John K. Ousterhout : CTSS : Multix OS Unix History : Unix shell history : VI editor : History of pipes concept : Solaris : MS DOS : Programming Languages History : PL/1 : Simula 67 : C : History of GCC development : Scripting Languages : Perl history : OS History : Mail : DNS : SSH : CPU Instruction Sets : SPARC systems 1987-2006 : Norton Commander : Norton Utilities : Norton Ghost : Frontpage history : Malware Defense History : GNU Screen : OSS early history
The Peter Principle : Parkinson Law : 1984 : The Mythical Man-Month : How to Solve It by George Polya : The Art of Computer Programming : The Elements of Programming Style : The Unix Hater’s Handbook : The Jargon file : The True Believer : Programming Pearls : The Good Soldier Svejk : The Power Elite
Most popular humor pages:
Manifest of the Softpanorama IT Slacker Society : Ten Commandments of the IT Slackers Society : Computer Humor Collection : BSD Logo Story : The Cuckoo's Egg : IT Slang : C++ Humor : ARE YOU A BBS ADDICT? : The Perl Purity Test : Object oriented programmers of all nations : Financial Humor : Financial Humor Bulletin, 2008 : Financial Humor Bulletin, 2010 : The Most Comprehensive Collection of Editor-related Humor : Programming Language Humor : Goldman Sachs related humor : Greenspan humor : C Humor : Scripting Humor : Real Programmers Humor : Web Humor : GPL-related Humor : OFM Humor : Politically Incorrect Humor : IDS Humor : "Linux Sucks" Humor : Russian Musical Humor : Best Russian Programmer Humor : Microsoft plans to buy Catholic Church : Richard Stallman Related Humor : Admin Humor : Perl-related Humor : Linus Torvalds Related humor : PseudoScience Related Humor : Networking Humor : Shell Humor : Financial Humor Bulletin, 2011 : Financial Humor Bulletin, 2012 : Financial Humor Bulletin, 2013 : Java Humor : Software Engineering Humor : Sun Solaris Related Humor : Education Humor : IBM Humor : Assembler-related Humor : VIM Humor : Computer Viruses Humor : Bright tomorrow is rescheduled to a day after tomorrow : Classic Computer Humor
The Last but not Least
Copyright © 1996-2016 by Dr. Nikolai Bezroukov. www.softpanorama.org was initially created as a service to the (now defunct) UN Sustainable Development Networking Programme (SDNP) in the author free time and without any remuneration. This document is an industrial compilation designed and created exclusively for educational use and is distributed under the Softpanorama Content License.
Original materials copyright belong to respective owners. Quotes are made for educational purposes only in compliance with the fair use doctrine.
FAIR USE NOTICE This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available to advance understanding of computer science, IT technology, economic, scientific, and social issues. We believe this constitutes a 'fair use' of any such copyrighted material as provided by section 107 of the US Copyright Law according to which such material can be distributed without profit exclusively for research and educational purposes.
This is a Spartan WHYFF (We Help You For Free) site written by people for whom English is not a native language. Grammar and spelling errors should be expected. The site contain some broken links as it develops like a living tree...
|You can use PayPal to make a contribution, supporting development of this site and speed up access. In case softpanorama.org is down you can use the at softpanorama.info|
The statements, views and opinions presented on this web page are those of the author (or referenced source) and are not endorsed by, nor do they necessarily reflect, the opinions of the author present and former employers, SDNP or any other organization the author may be associated with. We do not warrant the correctness of the information provided or its fitness for any purpose.
Last modified: September 12, 2017