Rotors of M-209 cipher machine.

General Cybersecurity Information

General Information About Cybersecurity

If your experience is at all like mine, you will find that you need to both educate and convince people — from the "on-the-front-lines" users to management. Here's some help. Tell them about telecommunications outages, big-money losses, cyberwar, COMSEC, and more. In the following list:
AWST = Aviation Week and Space Technology
WSJ = Wall Street Journal
DOD = U.S. Department of Defense

The 2012 NTP Outage

On November 19, 2012, the two stratum 1 NTP servers and went back in time by about 12 years. This caused outages in a wide range of PBXs, routers, and Active Directory servers. See NTP Issues Today at the NANOG mailing list, and Did Your Active Directory Domain Time Just Jump To The Year 2000? and Has your Windows Server 2003 Domain Controller time gone back to year 2000 (like Y2K)? at Microsoft's Technet.

Electromagnetic Pulse Myths: EMP and HERF Guns

There are constant dire warnings about electromagnetic pulse (or EMP) weapons. Here is an excellent collection of rebuttals and disproofs:
EMP Weapons: Keeping us fearful

This has been over-hyped with fictional stories at least since the mid 1990s. Back then there was a persistent claim that a London banking organization paid millions of pounds to stop a two-year series of attacks mixing logic bombs with electromagnetic pulse weapons. This was supposedly reported in the London Sunday Times, 2 June 1996, pg 1, and 9 June 1996, pg 1, but good luck finding the report. This story is now widely thought to be overly hyped and possibly a complete fabrication, especially the part about the electromagnetic pulse weapons. But self-proclaimed "infowar specialists" still carry on endlessly about "HERF guns" (or high-energy radio frequency weapons) and EMP devices.

GPS Spoofing


Reports of GPS spoofing by Russia became common in 2017. Also see the academic paper "Hostile Control of Ships via False GPS Signals: Demonstration and Detection", Jahshan Bhatti and Todd E. Humphreys, Navigation, doi://10.1002/navi.183.


Digital watermarking, related to steganography (hiding messages in data), has been around a long time:

Wasted Time

For huge losses most people willingly ignore, see Scientific American, July 1997, pp 82-89, for a great article, "Taking Computers to Task" by W. W. Gibbs. For example, Sun Microsystems prohibited fancy presentations, as they found that people can quickly assemble quality technical information but they will waste lots of time trying to make slides look pretty.

DNS (Domain Name System) Security Issues

DNS should work as follows:

  1. The human user types into a browser. The browser recognizes that this is not an IP address, and it makes a library call to the resolver. That creates a DNS query packet asking for an A record for the fully-qualified domain name (FQDN). This is a relatively simple UDP datagram.
  2. That DNS query is sent to the client's nameserver. If you are reading this at home, that means the DNS server specified by your ISP when your system used DHCP to get its IP configuration. If you are at work, then it would be your corporate DNS server. Either way, the DNS server is willing to do some work on behalf of the client and answer its questions because it's a client.
  3. That nameserver (labeled "ISP nameserver" below) doesn't know and it doesn't know who to ask. So it asks a server authoritative for the entire .com domain, "Where is the nameserver for the domain?", asking for an NS record. The root servers are authoritative for .com and so its IP address is coded into the DNS server software.
  4. The .com server answers the direct question and also passes along the answer to the obvious next question, "What are their IP addresses?". As it turns out, there are four. One question was asked, there were four answers and four additional pieces of useful information.
  5. Your nameserver now picks one of those servers and asks the original question, "What is the IP address for".
  6. That nameserver responds that is really an alias. The canonical name is and its IP address is This information should be good for a while, feel free to cache it for 3,600 seconds.
  7. Your ISP returns that information to your client, which receives it and passes the information along to the browser application. It makes a connection to TCP port 80 on that IP address, and this page loads.
  8. Meanwhile your nameserver is caching that information in case some client asks the question within the Time To Live value.

Below you see those numbered steps as ASCII art:

[1,2] client -------> ISP nameserver
              DNS query:
     A record

[3]                   ISP nameserver ------------> .com name server
				DNS query: NS

[4]                   ISP nameserver <------------ .com name server
				;; ANSWER SECTION:      18418   IN      NS      18418   IN      NS      18418   IN      NS      18418   IN      NS

				;; ADDITIONAL SECTION: 18418 IN AAAA    2001:4860:4802:32::6c 18418 IN AAAA    2001:4860:4802:34::6c 18418 IN AAAA    2001:4860:4802:36::6c 18418 IN AAAA    2001:4860:4802:38::6c 18418 IN A 18418 IN A 18418 IN A 18418 IN A

[5]			ISP nameserver ------------------------>
				DNS query: A

[6]			ISP nameserver <------------------------
				;; ANSWER SECTION:  3600    IN      CNAME      3600    IN      A

[7,8] client <------- ISP nameserver <---> cache
		DNS answer: CNAME =
		Additional resource record: A =
		TTL = 3600 seconds

What the attacker wants to do:
The attacker wants to fool many people into looking at the wrong web site. They build a bogus web site on some server. It looks like something people would trust, for example, a clone of the web site. Of course, it is just going to steal information if anyone visits it and believes it's really Citibank!

They will then try to fool as many DNS servers as possible into beliving that the IP address for and is whatever IP address they have for their bogus site.

So how do the bad guys fool the world-wide DNS infrastructure?

Problem #1 — Stateless DNS
Early versions of the BIND DNS server did not keep track of which questions they had asked. If they got an answer, they assumed it was relevant and put it in the cache. So the bad guy does this:

Problem #2 — The Kaminsky DNS Vulnerability
Dan Kaminsky discovered a very serious problem in DNS and publicized it in the summer of 2008. Left out of the above explanation was the detail that DNS packets contain a field called the Query ID. This allows a DNS server to match answers to questions, and it allows newer DNS implementations with some sense of state to tell if a given answer corresponds to a question that they had asked.

The problem is that the Query ID is reasonably easy to guess in many DNS server implementations. The bad guy now:

This is also a cache poisoning attack, but it is far more powerful.

So, how do you avoid being a victim?

The djbdns DNS server by Daniel J Bernstein has correctly randomized both the source UDP port and Query ID since the beginning. Many people find his djbdns easier to configure than the much more commonly used BIND software from ISC.

"Security through obscurity"

"Security through obscurity" has known to be ineffectual for well over a century. Auguste Kerckhoffs (1835-1903) stated that the security of a cryptosystem must not depend on keeping its algorithm secret. See his article "La cryptographie militaire", in Journal des sciences militaries, vol IX, pp 5-38, Jan 1883.
Overview The original paper (PDF)

U.S. Government fear-mongering about electrical power grid hacking

The U.S. Department of Homeland Security released a very contrived video in September 2007 showing catastrophic failure of an electrical power generator. This got notoriety as the "Aurora Generator Test", conducted in March 2007. But it was largely interpreted as little more than an intentional scare story by DHS.

Then "CIA senior analyst Tom Donahue" seems to have gone on a one-man fright crusade:

June 2008 — "Last month the National Journal cited two computer security professionals, who in turn cited unnamed U.S. intelligence officials, in reporting that China's People's Liberation Army may have cracked the computers controlling the U.S. power grid to trigger the cascading blackout that cut off electricity to 50 million people in eight states and a Canadian province [in August, 2003]" But cyber security consultant Paul Kurtz, who worked at the White House at the time of the blackout, said they're no truth to the claim and many others have backed him up.

April 2009 — This same story appeared, again, in the Wall Street Journal this time (4 April 2009, article by Siobhan Gorman). The article is based on anonymous sources and "former national-security officials". It goes on to re-hash "CIA senior analyst Tom Donahue", making this just yet another cycle of the same old scare story.

April 15, 2009 — Time magazine observes that there have been no instances of cyberattacks taking down national power grids.

It has been observed in a Wired article that these scary stories are suspiciously correlated with US Government announcements of the need for increased surveillance.

A more prominent threat is physical attacks. Some have taken place, see stories at the Los Angeles Times, Reuters, and the Wall Street Journal for reports on an April 2013 attack on the PG&E Metcalf substation near San Jose, California, when rifle shots damaged 17 transformers.

See the following section about attacks on infrastructure for things that really did happen.

Russian Business Network (RBN) cyber-crime organization

A 13 Oct 2007 Washington Post article "Shadowy Russian Firm Seen as Conduit for Cybercrime" reported, "An Internet business based in Saint Petersburg has become a world hub for Web sites devoted to child pornography, spamming and identity theft, according to computer security experts. They say Russian authorities have provided little help in efforts to shut down the company. The Russian Business Network sells Web site hosting to people engaged in criminal activity, the security experts say. Groups operating through the company's computers are thought to be responsible for about half of last year's incidents of "phishing" VeriSign said that the Rock Group phishers used RBN to steal about US$ 150 million over the preceding year. Symantec said that RBN was "responsible for hosting Web sites that carry out a major portion of the world's cybercrime and profiteering." RBN does not have its own web site, you must contact its operators via instant-messaging or obscure Russian-language online forums. You must also prove that you are not a law enforcement investigator by demonstrating active involvement in theft of consumers' financial and personal data.

Russky Newsweek described "the world of Russian hackers" in December 2009. It mentions the apparently connections between international conflict on the Internet between Russia and Estonia and Georgia, attacks against Citigroup, and massive identity theft and spamming. But it's still uncertain if RBN was really one criminal vast organization or if it was a host to multiple Internet based gangs. Interesting anecdotes in that article include:

U.S. military use of commercial telecommunication links

Early 1990s — "About 20% of satcom support for Operation Desert Storm came from commercial [satellite] fleets." AWST 19 Nov 2007 pp 52-53.

1995-1996 — 95% of military communication at least touches the public switched networks. DOD is primarily reactive with no uniform policy for assessing risks, protecting systems, responding to incidents, or assessing damage. Military and Aerospace Electronics, January 1997, pg 17; AWST, 13 Jul 1998, pp 67-70 (quoting Maj. Gen. John Casciano, USAF director of intelligence); Lt Gen Kenneth A Minihan, "Intelligence and Information System Security", Defense Intelligence Journal, vol 5 n 1 (Spring 1996), pg 20.

2007 — "Now about 80% of all satellite communications in Iraq and Afghanistan come from commercial spacecraft, which may in some cases simultaneously provide services to friendly forces, as well as adverseries. AWST 19 Nov 2007 pp 52-53.

2008 — "Roughly 85% of [U.S.] military satellite communications are processed by commercial entities, but those services are purchased in an ad hoc fashion." AWST Oct 13, 2008, pg 34.

A 19 Nov 2007 AWST article (pp 52-53) described the USAF 16th Space Control Squadron (SPCS), dedicated to "defensive counterspace" and detecting and locating jamming to satellite links. It says that the 16th SPCS, based at Peterson AFB in Colorado, operates the new Rapid Attack Identification Reporting System (Raidrs), alerting its operators of interference to satellite communications links at UHF and the microwave C, Ku and X bands. It's designed and manufactured by Integral Systems of Lanham, Maryland. Each Raidrs site includes up to six 2.4-meter dish antennas to monitor signals, and a 3.7-meter antenna connected to a Blackbird system, said to operate like a spectrum analyzer. Two more 4.5-meter antennas are said to locate the distant ground-based jamming or interference source. The article made it sound as if the location is done by precise measurement of uplink signals reflected from the satellite bodies of the intended relay satellite and another satellite in a nearby orbit — an impressive achievement if correct.

USB storage devices and issues for the military

"Colombia's struggling guerrila movement appears to have suffered yet another defeat because of technology. The names of more than 9,000 rebels have fallen into government hands. Two government officials said this week [26 Sep 2008] that soldiers raiding a rebel camp in February [2008] found a memory stick that held the names, aliases and identity numbers of 9,387 rebels — and even included the photos of some of them." The group was FARC, the Revolutionary Armed Forces of Columbia. New York Times 26 Sep 2008, pg A8.

USB storage devices have been stolen from U.S. military bases in Afghanistan by local cleaning staff and sold in the local bazaars through the 2000s. Stories were carried by the BBC and the Los Angeles Times.

Attacks against infrastructure, many mentioned in the article found here. Meanwhile, do not be frightened by apparently weak claims of hacker attacks on the U.S. power network, debunked in elsewhere on this page.

And pipelines and sewers and ...

The classic story is Agent Farewell and the Siberian Pipeline Explosion, in which an explosion around the end of October 1982 in the middle of Siberia "vaporized a large segment of the newly-build trans-Siberian pipeline". Thomas Reed's At the Abyss: An Insider's History of the Cold War describes the U.S. CIA working with a Canadian supplier to compromise the system's SCADA software with a logic bomb. The resulting explosion is enthusiastically described as "visible from space" and "1/7 the magnitudes of the nuclear weapons dropped on Japan during WWII". (combined? each?) See the National Security Archive report for a fairly calm description, and also see the CIA's Center for the Study of Intelligence report. Despite the American enthusiasm for the supposed cataclysm, there were no known physical casualities and seems to have gone unknown to the Soviet public.

1999 — Malicious hackers took control of a Gazprom gas pipeline in Russia for around 24 hours.

2000 — A disgruntled ex-employee accessed the industrial control systems of a sewage treatment plant in Maroochy Shire, Queensland, Australia, and released at least a million liters of raw sewage into a river and onto the grounds of a hotel. From a detailed article:
"Located in a tourist area on the east coast, the sewage system has 142 pumping stations connected by radio to monitoring computers.
The troubles began when the installation company, Hunter Watertech, finished installing the control system in December 1999 and the site supervisor for HWT, Vitek Boden, resigned 'under circumstances that are not exactly explained'. He applied to MSC for a position, but was rejected.
The following month, January 2000, strange things started to happen. Pumps were not running when needed, alarms were not being reported to the control centre, and there was a loss of communications between the control centre and the pumping stations.
The evidence began to point to outside agents interfering with the system. With data logging this became more apparent when engineers noticed a spoofed pump station ID. The system was receiving signals from a pumping station ID that wasn't where it should have been — and it wasn't sending the right sort of signals. After inspecting one particular pump station site and re-coding its ID, it became clear that they were receiving signals coming in from a station that didn't exist. Radio monitoring was also starting to detect these transmissions. After nearly two months of baffling problems, on 16 March they began to get some hard evidence of what was going on. They spotted radio transmissions controlling various pump stations from the fake ID.
By this time, in the middle of March, a lot of faults were occurring and it was obvious that the hacker wasn't just playing around with the control system. There were sewage leaks, caused by overflowing tanks when pumps were turned off. The golf course next to the Hyatt Hotel was flooded with a million litres of sewage. A major overflow into a residential area and tidal canal polluted an estuary; in the surrounding area on Australia's Sunshine Coast, creeks turned black and cost the government Au$100,000 to set up an environmental monitoring programme."

Also see "Malicious Control System Cyber Security Attack Case Study — Maroochy Water Services, Australia".

2003 — The "Slammer" worm disabled a safety monitoring system at Davis-Basse nuclear power plant in Ohio, USA. Of course, this was not the original intent of the attack.

2007 — A former employee for a federally-owned canal system in California was charged with installing software that damaged a computer used to divert water out of a local river, as described in The Register. The Tehama Colusa Canal Authority operates two canals that move water out of the Sacramento River for use in irrigation and agriculture in Northern California. The perpetrator worked for the TCCA for more than 17 years before being fired on August 15, the date he is alleged to have installed the unauthorized software.

2007 — Lonnie Charles Denison was a SAIC contractor working as a UNIX systems administrator at the California Independent System Operator's data center controlling California's power grid. He had a dispute with his boss at SAIC and learned on 15 April that he had lost computer access privileges. Minutes later he broke a glass cover and hit the emergency power "off" button, shutting down the facility. This cut California off from the wholesale electricity market (although it did not cut off power to the state!). Allegedly he e-mailed a bomb threat the next day to a California ISO employee. In December he pled guilty, and faced up to five years in prison and $250,000 in fines.
The Register, 20 Apr 2007; Computerworld, 1 Jan 2008, pg 6; PC World and several other sources]

2010 — The Stuxnet worm was detected in June, 2010. This eventually led to many more discoveries of malicious software, eventually attributed to the U.S., see the cyberwar page for the details.

Read this good article about "The Great Firewall of China", the national firewall in People's Republic of China from The Atlantic Monthly.

In May 1998 an internal review of DOE facilities found serious security problems (classified info on open systems, anonymous ftp write permission, readable password files, etc) on 1,400 of 64,000 systems. Los Alamos had detected 15 security breaches in the preceding 6 months. Brock Meeks, MSNBC, 29 May 1998, Stark Abstracting.

Hardware cryptographic attacks — The Electronic Frontier Foundation developed and built a dedicated platform in 1998 for under US$ 250,000 that breaks DES-encrypted messages in 72 hours, an order of magnitude faster than the best distributed network attack at the time. Much of the cost was design and development — the next one with the same performance would cost $50,000 or less. Speed to break DES on this architecture drops linearly with dollars spent on hardware, so forget all the U.S. government claims about hardware solutions being impossible. Also remember that this is cost for today's hardware, and cost per performance falls fast over time. Click here for the EFF article.

Further References

Threats are under-reported, and that's no recent development:

ARPA/NSA/DISA/DSS Memorandum of Agreement for coordinating Infosec research programs

For current research and development, see Purdue's CERIAS group.

The classic Unix security paper is UNIX Operating System Security, in AT&T Bell Labs Technical Journal, October 1984.

See the Trusted Product Evaluation Program frequently-asked-question list on computer security.

Disaster recovery is a whole field in itself. Check out the Disaster Recovery Journal. For a light introduction, see IEEE Spectrum, December 1996, pg 49.

A very scholarly treatment of Internet congestion models is in Science,, vol 277, 25 July 1997, pp 477, 535-537.

Keep looking — here are some more web sites to check out.

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