Schneier on Security

Cisco Harasses Security Researcher

I’ve written about full disclosure, and how disclosing security vulnerabilities is our best mechanism for improving security—especially in a free-market system. (That essay is also worth reading for a general discussion of the security trade-offs.) I’ve also written about how security companies treat vulnerabilities as public-relations problems first and technical problems second. This week at BlackHat, security researcher Michael Lynn and Cisco demonstrated both points.

Lynn was going to present security flaws in Cisco’s IOS, and Cisco went to inordinate lengths to make sure that information never got into the hands of the their consumers, the press, or the public.

Cisco threatened legal action to stop the conference’s organizers from allowing a 24-year-old researcher for a rival tech firm to discuss how he says hackers could seize control of Cisco’s Internet routers, which dominate the market. Cisco also instructed workers to tear 20 pages outlining the presentation from the conference program and ordered 2,000 CDs containing the presentation destroyed.

In the end, the researcher, Michael Lynn, went ahead with a presentation, describing flaws in Cisco’s software that he said could allow hackers to take over corporate and government networks and the Internet, intercepting and misdirecting data communications. Mr. Lynn, wearing a white hat emblazoned with the word “Good,” spoke after quitting his job at Internet Security Systems Inc. Wednesday. Mr. Lynn said he resigned because ISS executives had insisted he strike key portions of his presentation.

Not being able to censor the information, Cisco decided to act as if it were no big deal:

In a release shortly after the presentation, Cisco stated, “It is important to note that the information Lynn presented was not a disclosure of a new vulnerability or a flaw with Cisco IOS software. Lynn’s research explores possible ways to expand exploitations of known security vulnerabilities impacting routers.” And went on to state “Cisco believes that the information Lynn presented at the Blackhat conference today contained proprietary information and was illegally obtained.” The statement also refers to the fact that Lynn stated in his presentation that he used a popular file decompressor to ‘unzip’ the Cisco image before reverse engineering it and finding the flaw, which is against Cisco’s use agreement.

The Cisco propaganda machine is certainly working overtime this week.

The security implications of this are enormous. If companies have the power to censor information about their products they don’t like, then we as consumers have less information with which to make intelligent buying decisions. If companies have the power to squelch vulnerability information about their products, then there’s no incentive for them to improve security. (I’ve written about this in connection to physical keys and locks.) If free speech is subordinate to corporate demands, then we are all much less safe.

Full disclosure is good for society. But because it helps the bad guys as well as the good guys (see my essay on secrecy and security for more discussion of the balance), many of us have championed “responsible disclosure” guidelines that give vendors a head start in fixing vulnerabilities before they’re announced.

The problem is that not all researchers follow these guidelines. And laws limiting free speech do more harm to society than good. (In any case, laws won’t completely fix the problem; we can’t get laws passed in every possible country security researchers live.) So the only reasonable course of action for a company is to work with researchers who alert them to vulnerabilities, but also assume that vulnerability information will sometimes be released without prior warning.

I can’t imagine the discussions inside Cisco that led them to act like thugs. I can’t figure out why they decided to attack Michael Lynn, BlackHat, and ISS rather than turn the situation into a public-relations success. I can’t believe that they thought they could have censored the information by their actions, or even that it was a good idea.

Cisco’s customers want information. They don’t expect perfection, but they want to know the extent of problems and what Cisco is doing about them. They don’t want to know that Cisco tries to stifle the truth:

Joseph Klein, senior security analyst at the aerospace electronic systems division for Honeywell Technology Solutions, said he helped arrange a meeting between government IT professionals and Lynn after the talk. Klein said he was furious that Cisco had been unwilling to disclose the buffer-overflow vulnerability in unpatched routers. “I can see a class-action lawsuit against Cisco coming out of this,” Klein said.

ISS didn’t come out of this looking very good, either:

“A few years ago it was rumored that ISS would hold back on certain things because (they’re in the business of) providing solutions,” [Ali-Reza] Anghaie, [a senior security engineer with an aerospace firm, who was in the audience,] said. “But now you’ve got full public confirmation that they’ll submit to the will of a Cisco or Microsoft, and that’s not fair to their customers…. If they’re willing to back down and leave an employee … out to hang, well what are they going to do for customers?”

Despite their thuggish behavior, this has been a public-relations disaster for Cisco. Now it doesn’t matter what they say—we won’t believe them. We know that the public-relations department handles their security vulnerabilities, and not the engineering department. We know that they think squelching information and muzzling researchers is more important than informing the public. They could have shown that they put their customers first, but instead they demonstrated that short-sighted corporate interests are more important than being a responsible corporate citizen.

And these are the people building the hardware that runs much of our infrastructure? Somehow, I don’t feel very secure right now.

EDITED TO ADD: I am impressed with Lynn’s personal integrity in this matter:

When Mr. Lynn took the stage yesterday, he was introduced as speaking on a different topic, eliciting boos. But those turned to cheers when he asked, “Who wants to hear about Cisco?” As he got started, Mr. Lynn said, “What I just did means I’m about to get sued by Cisco and ISS. Not to put too fine a point on it, but bring it on.”

And this:

Lynn closed his talk by directing the audience to his resume and asking if anyone could give him a job.

“In large part I had to quit to give this presentation because ISS and Cisco would rather the world be at risk, I guess,” Lynn said. “They had to do what’s right for their shareholders; I understand that. But I figured I needed to do what’s right for the country and for the national critical infrastructure.”

There’s a lawsuit against him. I’ll let you know if there’s a legal defense fund.

EDITED TO ADD: The lawsuit has been settled. Some details:

Michael Lynn, a former ISS researcher, and the Black Hat organisers agreed to a permanent injunction barring them from further discussing the presentation Lynn gave on Wednesday. The presentation showed how attackers could take over Cisco routers, a problem that Lynn said could bring the Internet to its knees.

The injunction also requires Lynn to return any materials and disassembled code related to Cisco, according to a copy of the injunction, which was filed in US District Court for the District of Northern California. The injunction was agreed on by attorneys for Lynn, Black Hat, ISS and Cisco.

Lynn is also forbidden to make any further presentations at the Black Hat event, which ended on Thursday, or the following Defcon event. Additionally, Lynn and Black Hat have agreed never to disseminate a video made of Lynn’s presentation and to deliver to Cisco any video recording made of Lynn.

My hope is that Cisco realized that continuing with this would be a public-relations disaster.

EDITED TO ADD: Lynn’s BlackHat presentation is on line.

EDITED TO ADD: The FBI is getting involved.

EDITED TO ADD: The link to the presentation, above, has been replaced with a cease-and-desist letter. A copy of the presentation is now here.

Posted on July 29, 2005 at 4:35 AM • View Comments