Essays: 2001 Archives

Banners and Internet Protocols

You may already be vulnerable

  • Bruce Schneier
  • Dr. Dobb's Journal
  • November 2001

It used to be that when you connected to one of Counterpane’s mailers, it responded with a standard SMTP banner that read something like the following:

220 ESMTP Sendmail 8.8.88. 7.5; Mon, 7 May 2001 21:13:35 0600 (MDT

Because this information includes a Sendmail version number, some people sent us mail that read (loosely interpreted): “Heh, heh, heh. Bruce’s company runs a stupid Sendmail!”

Until recently, our IT staffs standard response was to smile and say, “Yes, that certainly is what the banner says,” leaving the original respondent to wonder why we didn’t care. (There are a bunch of reasons we don’t care, and explaining them would take both the amusement and security out of it all.)…

Protecting Privacy and Liberty

The events of 11 September offer a rare chance to rethink public security.

  • Bruce Schneier
  • Nature
  • October 25, 2001

Appalled by the events of 11 September, many Americans have declared so loudly that they are willing to give up civil liberties in the name of security that this trade-off seems to be a fait accompli. Article after article in the popular media debates the ‘balance’ of privacy and security—are various types of increase in security worth the consequent losses to privacy and civil liberty? Rarely do I see discussion about whether this linkage is valid.

Security and privacy are not two sides of an equation. This association is simplistic and largely fallacious. The best ways to increase security are not at the expense of privacy and liberty. Giving airline pilots firearms, reinforcing cockpit doors, better authentication of airport maintenance workers, armed air marshals travelling on flights and teaching flight attendants karate are all examples of suggested security measures that have no effect on individual privacy or liberties…

Efforts to Limit Encryption Are Bad for Security

  • Bruce Schneier
  • InternetWeek
  • October 1, 2001

In the wake of the devastating attacks on New York’s World Trade Center and the Pentagon, Sen. Judd Gregg (R-N.H.), with backing from other high- ranking government officials, quickly seized the opportunity to propose limits on strong encryption and “key-escrow” systems that insure government access. This is a bad move because it will do little to thwart terrorist activities and it will also reduce the security of our critical infrastructure.

As more and more of our nation’s critical infrastructure goes digital, cryptography is more important than ever. We need all the digital security we can get; the government shouldn’t be doing things that actually reduce it. We’ve been through these arguments before, but legislators seem to have short memories. Here’s why trying to limit cryptography is bad for e-business:…

The Real Lesson of Code Red: Insecurity Is a Way of Life

  • Bruce Schneier
  • InternetWeek
  • September 3, 2001

Most people don’t understand the real lessons of Code Red II.

Code Red II could have been much worse. As it had full control of every machine it took over, it could have been programmed to do anything, including dropping the entire Internet. It could have spread faster and been stealthier. It could have exploited several vulnerabilities, not just one. It could have been polymorphic.

Code Red II left a lot of questions unanswered. What will come in when Code Red II installs a back door and drops a Trojan program in vulnerable computers? Will there be a Code Red III? What will it do? What about Code Red XXVII?…

Arrest of Computer Researcher Is Arrest of First Amendment Rights

  • Bruce Schneier
  • InternetWeek
  • August 6, 2001

The arrest of a Russian computer security researcher was a major setback for computer security research. The FBI nabbed Dmitry Sklyarov after he presented a paper at DefCon, the hacker community convention in Las Vegas, on the strengths and the weaknesses of software to encrypt an electronic book.

Although I’m certain the FBI’s case will never hold up in court, it shows that free speech is secondary to the entertainment industry’s paranoia about copyright protection.

Sklyarov is accused of violating the Digital Millennium Copyright Act (DMCA), which makes publishing critical research on this technology more serious than publishing design information on nuclear weapons…

Testimony before the Senate Subcommittee on Science, Technology, and Space

  • Bruce Schneier
  • July 16, 2001

Testimony and Statement for the Record of Bruce Schneier
Chief Technical Officer, Counterpane Internet Security, Inc.

Hearing on Internet Security before the Subcommittee on Science, Technology, and Space of the Committee on Commerce, Science and Transportation

United States Senate

July 16, 2001
253 Russell Senate Office Building

My name is Bruce Schneier. I am the founder and Chief Technical Officer of Counterpane Internet Security. Inc. Counterpane was founded to address the immediate need for increased Internet security, and essentially provides burglar alarm services for computer networks. I am the author of seven books on cryptography and computer security, as well as hundreds of articles and papers on those topics. For several years, I have been a security consultant to many major Internet companies…

Marriage Of Phone Services, Biz Apps Could Be A Security Risk

  • Bruce Schneier
  • InternetWeek
  • July 9, 2001

One of the key reasons businesses have yet to link their business applications with telephone services is there’s no common interface. While two standards under development promise to let businesses integrate and control telephony services, such as call forwarding and automatic number identification, with software, such as Web-based call center apps, these standards could introduce huge security risks.

These standards address key issues. One organization working in this space is The Parlay Group (, a consortium of software, hardware and telecommunication service providers. The group is creating a specification and an application programming interface that will enable phone-system control from outside the secure telco network. This interface can be embedded in applications to reroute calls, provide notification of call attempts, retrieve the location of mobile users and link to telco billing systems, among other features…

In War Against Cyberspace Intruders, Knowledge Is Power

  • Bruce Schneier
  • InternetWeek
  • June 18, 2001

In warfare, information is power. The better you understand your enemy, the more able you are to defeat him.

In the war against malicious hackers, network intruders and the other black-hat denizens of cyberspace, the good guys have surprisingly little information. Most security experts-even those who design products to protect against attacks-are ignorant of the tools, tactics and motivations of the enemy.

The Honeynet Project, a group of 30 researchers from academia and the commercial sector, is trying to change that. The group obtains information through the use of a Honeynet-a computer network on the Internet that’s designed to be compromised. The network is made up of various production systems complete with sensors as well as a suitably enticing name and content. (The actual IP address changes regularly and isn’t published.) Hackers’ actions are recorded as they happen: how the culprits try to break in, when they’re successful and what they do when they succeed…

Computer Security Standards Aren't Scoring In The Commercial World

  • Bruce Schneier
  • InternetWeek
  • May 14, 2001

Despite numerous efforts over the years to develop comprehensive computer security standards, it’s a goal that remains elusive at best.

As far back as 1985, the U.S. government attempted to establish a general method for evaluating security requirements. This resulted in the “Orange Book,” the colloquial name for the U.S. Department of Defense Trusted Computer System Evaluation Criteria. The Orange Book gave computer manufacturers a way to measure the security of their systems and offered a method of classifying different levels of computer security…

Foreword to Security Engineering by Ross Anderson

  • Bruce Schneier
  • May 2001

In a paper he wrote with Roger Needham , Ross Anderson coined the phrase “programming Satan’s computer” to describe the problems faced by computer-security engineers. It’s a phrase I’ve used ever since.

Programming a computer is straightforward: keep hammering away at the problem until the computer does what it’s supposed to do. Large application programs and operating systems are a lot more complicated, but the methodology is basically the same. Writing a reliable computer program is much harder, because the program needs to work even in the face of random errors and mistakes: Murphy’s computer, if you will. Significant research has gone into reliable software design, and there are many mission-critical software applications that are designed to withstand Murphy…

Body of Secrets by James Bamford

The author of a pioneering work on the NSA delivers a new book of revelations about the mysterious agency's coverups, eavesdropping and secret missions.

  • Bruce Schneier
  • Salon
  • April 25, 2001

In 1982, James Bamford published “The Puzzle Palace,” his first exposé on the National Security Agency. His new exposé on the NSA is called “Body of Secrets.” Twenty years makes a lot of difference in the intelligence biz.

During those 20 years, the Reagan military buildup came and went, the Soviet Union fell and the Cold War ended, and a bevy of new military enemies emerged. Electronic communications exploded through faxes, cellphones, the Internet, etc. Cryptography came out of the shadows to become an essential technology of the networked world. And computing power increased ten thousand-fold…

IT Must Be More Vigilant About Security, Survey Shows

  • Bruce Schneier
  • InternetWeek
  • April 16, 2001

Despite huge investments by corporations in computer security infrastructure, an overwhelming majority of companies are finding that their networks are still being compromised. And there’s no reason to believe this will change anytime soon.

About 64 percent of companies’ systems have been victims of some form of unauthorized access, according to a recent survey by the Computer Security Institute (CSI). While 25 percent said they had no breaches and 11 percent said they didn’t know, I’d bet the actual number of companies that have been compromised is much higher…

Cyber Underwriters Lab?

  • Bruce Schneier
  • Communications of the ACM
  • April 2001

Underwriters Laboratories (UL) is an independent testing organization created in 1893, when William Henry Merrill was called in to find out why the Palace of Electricity at the Columbian Exposition in Chicago kept catching on fire (which is not the best way to tout the wonders of electricity). After making the exhibit safe, he realized he had a business model on his hands. Eventually, if your electrical equipment wasn’t UL certified, you couldn’t get insurance.

Today, UL rates all kinds of equipment, not just electrical. Safes, for example, are rated based on time to crack and strength of materials. A “TL-15” rating means that the safe is secure against a burglar who is limited to safecracking tools and 15 minutes’ working time. These ratings are not theoretical; employed by UL, actual hotshot safecrackers take actual safes and test them. Applying this sort of thinking to computer networks—firewalls, operating systems, Web servers—is a natural idea. And the newly formed Center for Internet Security (no relation to UL) plans to implement it…

Back Door Security Threat in Interbase Teaches Broader Lessons

  • Bruce Schneier
  • InternetWeek
  • March 12, 2001

When a hacker adds a back door to your computer systems for later unauthorized access, that’s a serious threat. But it’s an even bigger problem if you created the back door yourself.

It seems that Borland did just that with its Interbase database. All versions released for the past seven years (versions 4.x through 6.01) have a back door. And, by extension, so do all their customers. How it came about and how it was discovered should serve as a lesson to all IT managers.

Versions of Interbase before 1994 didn’t have any access-control mechanisms. When the company added access control in version 4.0, it used a peculiar system. The engineers created a special database within Interbase for account names and encrypted passwords. This solution created a new problem: In order to authenticate a user, the program had to access the database; but before the program could access the database, it had to authenticate a user…

Insurance and the Computer Industry

  • Bruce Schneier
  • Communications of the ACM
  • March 2001

View or Download in PDF Format

In the future, the computer security industry will be run by the insurance industry. I don’t mean insurance companies will start selling firewalls, but rather the kind of firewall you use—along with the kind of authentication scheme you use, the kind of operating system you use, and the kind of network monitoring scheme you use—will be strongly influenced by the constraints of insurance.

Consider security and safety in the real world. Businesses don’t install alarms in their warehouses because it makes them safer; they do it because they get a break in their insurance rates. Hotels and office buildings don’t install sprinkler systems because they’re concerned about the welfare of their tenants, but because building codes and insurance policies demand it. These are all risk management decisions, and the risk-taker of last resort is the insurance industry…

PGP's Vulnerabilities Reveal the Truth about Security

  • Bruce Schneier
  • InternetWeek
  • February 12, 2001

Reports that PGP, a standard used to encrypt e-mail, is broken are greatly exaggerated. Although a recent criminal investigation has led some to conclude that flaws in the PGP protocol helped the FBI nab its suspect, the truth is that no one has broken the cryptographic algorithms that protect PGP traffic. And no one has discovered a software flaw in the PGP program that would allow someone to read PGP- encrypted traffic. All that happened was that someone installed a keyboard sniffer on a computer, letting that someone eavesdrop on every keystroke the user made. The sniffer let the eavesdropper pick up the PGP passphrase and the text of a victim’s messages as he typed…

The Insurance Takeover

  • Bruce Schneier
  • Information Security
  • February 2001

Eventually, the insurance industry will subsume the computer security industry. Not that insurance companies will start marketing security products, but rather that the kind of firewall you use—along with the kind of authentication scheme you use, the kind of operating system you use and the kind of network monitoring scheme you use—will be strongly influenced by the constraints of insurance.

Consider security, and safety, in the real world. Businesses don’t install building alarms because it makes them feel safer; they do it to get a reduction in their insurance rates. Building owners don’t install sprinkler systems out of affection for their tenants, but because building codes and insurance policies demand it. Deciding what kind of theft and fire prevention equipment to install are risk management decisions, and the risk taker of last resort is the insurance industry…

Gimmicks Won't Protect Your Digital Assets from Being Copied

  • Bruce Schneier
  • InternetWeek
  • January 22, 2001

Hacking contests are a popular way for software companies to demonstrate claims of how good their security products are in practice. But companies looking to protect their digital assets shouldn’t give too much credence to these challenges.

These contests typically involve a group or vendor offering money to anyone who can break through its firewall, crack its algorithm or make a fraudulent transaction using its technology. The Secure Digital Music Initiative (SDMI), an industry group that’s developed encryption methods to protect the copying of digital music files, issued a hacking challenge in September, offering $10,000 to anyone who could strip various copy-protection technologies out of songs provided as examples. SDMI put forth six different technologies, and already researchers from Princeton and Rice Universities and Xerox’s Palo Alto Research Center claim to have broken four of them. The SDMI disagrees, saying that only two were successfully hacked. Finger- pointing and jeering continue…

Sidebar photo of Bruce Schneier by Joe MacInnis.