Does the recent RSA attack make you less safe? You weren’t that safe to begin with.


Competing equipment vendors and security consultants are having a field day promoting the usual end of the world scenarios.  If you believe them, you should be wringing your hands because a major pillar of your security has been knocked down.

It’s just not true.  Your tokens weren’t providing you with that much security to begin with.

As the authors of the Zeus and similar trojans are gleefully aware, the security of one-time passwords is totally dependent on the security of the host system; that is, the PC you’re using to enter your one-time password (OTP).  And the host system is easily compromised with key loggers or similar malware.  Your OTP can be captured and quickly transmitted to an attacker. Or even easier, they can simply piggyback on your authenticated session.  So attackers have learned that rather than trying to guess your OTP, they can simply render them immaterial by side stepping the whole process.

Even if the host system can be trusted, the risk of an attacker guessing the OTP is quite low.  Let’s assume the attacker has knowledge of your token key and has a range of serial numbers.  That, along with your PIN and the time, will give him enough information to generate a correct password.  But a range of serial numbers, dozens to thousands, multiplied by the range of even a four digit PIN (many people seem to be surprised that they can be much longer) still gives you a key space in the millions.
Now of course, an automated script can try millions of passwords in just a few seconds.  But there’s no reason why you should give your attackers that many chances.  That’s like playing the lottery, and tickets are free.  Instead, simply limit the number of password tries to a small number, say 5-10.  You should have your systems lock out the account for a short period of time and alert you if there are too many password attempts.  That will effectively stop password guessing.

Token-based authentication using standard PCs is more about giving your users warm fuzzies rather than providing real security.  The RSA attack ultimately won’t affect your system security.

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Nick Kelly

Cybersecurity Engineer, Cisco

Nick has over 20 years of experience in Security Operations and Security Sales. He is an avid student of cybersecurity and regularly engages with the Infosec community at events like BSides, RVASec, Derbycon and more. The son of an FBI forensics director, Nick holds a B.S. in Criminal Justice and is one of Cisco’s Fire Jumper Elite members. When he’s not working, he writes cyberpunk and punches aliens on his Playstation.


Virgilio “BONG” dela Cruz Jr.

CCDP, CCNA V, CCNP, Cisco IPS Express Security for AM/EE
Field Solutions Architect, Tech Data

Virgilio “Bong” has sixteen years of professional experience in IT industry from academe, technical and customer support, pre-sales, post sales, project management, training and enablement. He has worked in Cisco Technical Assistance Center (TAC) as a member of the WAN and LAN Switching team. Bong now works for Tech Data as the Field Solutions Architect with a focus on Cisco Security and holds a few Cisco certifications including Fire Jumper Elite.


John Cavanaugh

CCIE #1066, CCDE #20070002, CCAr
Chief Technology Officer, Practice Lead Security Services, NetCraftsmen

John is our CTO and the practice lead for a talented team of consultants focused on designing and delivering scalable and secure infrastructure solutions to customers across multiple industry verticals and technologies. Previously he has held several positions including Executive Director/Chief Architect for Global Network Services at JPMorgan Chase. In that capacity, he led a team managing network architecture and services.  Prior to his role at JPMorgan Chase, John was a Distinguished Engineer at Cisco working across a number of verticals including Higher Education, Finance, Retail, Government, and Health Care.

He is an expert in working with groups to identify business needs, and align technology strategies to enable business strategies, building in agility and scalability to allow for future changes. John is experienced in the architecture and design of highly available, secure, network infrastructure and data centers, and has worked on projects worldwide. He has worked in both the business and regulatory environments for the design and deployment of complex IT infrastructures.