Thu 28 Jul 2005
Security researcher quits job and blows whistle on Cisco’s fatal flaws
Posted by glenn under Info WarCory Doctorow, BoingBoing, reports:
Michael Lynn is a security researcher who worked at the security firm ISS until yesterday. Now he’s under a restraining order from Cisco, arising from his disclosure of critical flaws in Cisco’s routers that threaten the world’s information infrastructure.
Lynn had found a buffer overflow exploit that lets an attacker take absolute control over Cisco routers. He sent the details to Cisco in April, but they still have not fully repaired the vulnerability. Since many of the world’s key routers are supplied by Cisco, this means Cisco’s foot-dragging places large parts of the world’s information infrastructure at grave risk of collapse.
Lynn proposed to disclose this vulnerability at Black Hat, the respected Las Vegas security conference. Cisco threatened to sue, claiming they were defending their “intellectual property.”
The conference and Lynn’s employer agreed to yank the presentation, and Cisco employees spent eight hours ripping Lynn’s research out of the printed program books before they were handed out to attendees. Lynn agreed to give a different talk.
Then, fewer than two hours before his presentation, Lynn announced his resignation from ISS. He got up on stage and delivered his original presentation. Cisco went ballistic and got a restraining order against Lynn and the conference forbidding them from further discussing this.
This SecurityFocus article is amazing — the gutsy quotes from Lynn in particular are inspiring. This guy is my new hero.
“I feel I had to do what’s right for the country and the national infrastructure,” he said. “It has been confirmed that bad people are working on this (compromising IOS). The right thing to do here is to make sure that everyone knows that it’s vulnerable…”
Lynn outlined a way to take control of an IOS-based router, using a buffer overflow or a heap overflow, two types of memory vulnerabilities. He demonstrated the attack using a vulnerability that Cisco fixed in April. While that flaw is patched, he stressed that the attack can be used with any new buffer overrun or heap overflow, adding that running code on a router is a serious threat.
“When you attack a host machine, you gain control of that machine–when you control a router, you gain control of the network,” Lynn said…
“It is especially regretful, and indefensible, that the Black Hat Conference organizers have given Mr. Lynn a platform to publicly disseminate the information he illegally obtained,” [CIsco] said in a statement. “We appreciate the cooperation we have received from ISS in this matter. We are working with ISS to continue our joint research in the area of security vulnerabilities…”
In the latest case, ISS and Lynn contacted Cisco in April to report their process for using a vulnerability in IOS to run a program on a Cisco router. The networking fixed the vulnerability in the operating system, but did nothing to prevent attackers from running programs on the devices using the broad techniques Lynn described, the researcher said.
During his presentation, Lynn outlined an eight step process using any known, but unpatched flaw, to compromise a Cisco IOS-based router. While he did not publish any vulnerabilities, Lynn said that finding new flaws would not be hard…
“What I just did means that I’m about to get sued by Cisco and ISS,” Lynn said, joking later that he may be “in Guantanamo” by the end of the week…
“What politicians are talking about when they talk about the Digital Pearl Harbor is a network worm,” he said. “That’s what we could see in the future, if this isn’t fixed.”
Update: James sez, “I am a source close to Mr. Lynn.
“Things to note: Lynn and ISS contacted Cisco about this vulnerability in April and it was fixed. Vulnerable versions are no longer available from Cisco. Cisco and ISS both initially support Lynn’s presentation at Black Hat. Cisco had, initially, commited to sending a representative to corraborate Lynn’s findings. Lynn had been planning to give this presentation since then, which was months in advance, with the consent of both ISS and Cisco.
“On Monday before the conference Cisco and ISS decided to pull the presentation with vague reasons given. This prompted the actions by Lynn on Wednesday, resignation and release.
“It is important to note and propogate that Lynn did go through the corrrect channels for release: he contacted the vendor, the vendor issued a fix. At this point, normally, public release would be allowed and expected.”