Dark Reading

If you think biometric scans are necessarily secure, think again: A European researcher has built a biometric keylogger that can capture fingerprint or other scans.

The so-called Biologger intercepts biometric data sent between a biometric scanner and its processing server, says Matt Lewis, a researcher with Information Risk Management, who demonstrated the tool and released proof-of-concept source code for it last week at Black Hat Europe in Amsterdam.

“It is the biometric equivalent of a traditional keylogger,” Lewis says. Biologger easily captures the biometric traffic, which then can be taken offline for the attacker to analyze and to find ways to subvert the biometric system, he says, adding that an attacker could use that information to recreate a user’s raw biometric image.

The attacker then could use that biometric to stage a spoofing attack, or to open a locked door, for instance, he says. “For example, if the system is a physical access control solution, then it may be possible to replay control signals that open locked doors, without the requirement for the presence of a valid biometric."

Lewis says an attacker could configure Biologger in several ways -- for sniffing biometric devices in a domain; as an inline wire tap or proxy device; for ARP poisoning; and as a memory-resident keylogger on a host. But planting Biologger in the victim network isn’t so easy: “Biologging as an attack vector is trivial. The difficult part might be getting the Biologger onto a network," he says.

“This could be done through physical means, or if the circumstances permitted, through exploitation of vulnerabilities via the Internet."

So what exactly is Biologger exploiting? The fact that many biometric systems don’t encrypt biometric data during the authentication process, according to Lewis. “Strong encryption of all biometric-related data during all transactions is the best way to defend against the attacks described in my paper,” he says. “This includes encryption over the network, and when storing biometric data in back-end databases.”

Lewis says biometrics isn’t about security: “Biometrics can work incredibly well under the right circumstances. It is just important that proper security controls are placed around biometric systems, as the biometric component alone cannot be relied upon for security."

Biologger is also aimed at building a penetration testing tool for biometric systems, he says -- capturing the traffic would be the core component of such a test.

Lewis says the Biologger source code he released is merely a POC of a proxy that captures data. “The aim of the POC was to highlight the simplicity of biologging, and how strong encryption would go a long way in protecting against the types of attacks that can be executed as a result of intercepted and unencrypted biometric data."

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