Security Musings

What a week!

WPA2 has been proven vulnerable to nonce reuse: reinstall and old key as a new key and it starts using the old nonces again. Nonce (a number used only once) is a key concept in the AES cipher. I think most issues implementations have with AES are related to handling nonces and making sure they never are used twice. Nonce has also been central to the Bluetooth mesh architecture and the way it is designed makes the mesh stand apart from other low power communication systems - we have a nonce that is never reset and still occupies effectively only 3 octets in a message. See Section 3.8.5 for details.

But that nonce problem in WiFi is not really a serious problem... Because who cares today if a WiFi network is secure or not? Airports, cafes, public hotspots... do we ever really rely on security of these? The answer is no. We rely on the security of our devices and on end-to-end protocols. We've reached the LAN's end. WiFi should not bother about security anymore - it'd be just easier to use...

Scared by system security breaches, people still voluntarily leak tons of information via email. It is so easy to send an email to a wrong address - a single typo and bam! Off it went falling into somebody's hands. In my organization I'm assigned the so called "catch-all" address. Meaning if an email arrives with a recipient address that does not exist (a typo or a person that no longer works with us), I'm getting that email. So for example, among important business emails with misspelled addresses, I'm getting tons of emails from Uber with ride receipts for people who used their business email for their private Uber accounts, while working with us. Now as they no longer are with the organization, and their email addresses are inactive, such emails leak the private lives of these people (when and where they travel...) and they don't seem to care to stop that... by updating their Uber accounts... So no matter how secure WiFi they use and how secure the Uber system is, a careless misconfiguration of notifications creates a leak...

The vulnerable RSA generation problem reported last week is much worse. Because it is about authentication and identity. It undermines the whole concept of non-repudiation: I used my electronic ID to buy a house and now the seller says they cannot be sure it was me or another person, as anyone could generate a private key that matches the public one on file.

Security continues to be challenging... We, as the industry, are learning quickly, but the incidents like the two that happened last week just show we have still a long way to go...