30 July 2007, 13:44

German security specialist refused entry to the USA

German security expert and reverse engineer Thomas Dullien of Sabre Labs, better known by his pseudonym of Halvar Flake, has revealed that he has been refused entry to the USA for the forthcoming Black Hat conference. Following a four and a half-hour interview with immigration authorities, he was sent home. Flake had been engaged by the conference organisers to give a session on "Analyzing Software for Security Vulnerabilities" as part of a series of pre-conference training sessions. According to Flake's blog entry on the incident, numerous representatives of US government agencies were due to take part in the session.

He was apparently refused entry because he did not have an H1B visa, required for such activities. Dullien states that he has travelled to Black Hat training sessions without a visa for years under the terms of the visa waiver program. He appears to have simply been fortunate that no-one noticed that, from the point of view of the immigration authorities, he was an employee of the Black Hat conference for this period. This time, however, this circumstance did not escape their notice, because Dullien was carrying paper copies of documentation for the training session in his hand baggage, which was checked by the immigration authorities. Flake states in his blog that the special contractual relationship between Black Hat and himself as a private person appears to have formed the basis for the objection. As a contractor within the scope of his employment for Sabre Labs, the problem would not have arisen. In addition, he says that officials repeatedly asked him why the training session was not being given by a US citizen.

Flake now intends to apply for a business visa, which takes between 4 days and 6 weeks. It is not clear who is now going to give the course, which costs 2400 US dollars to attend.