Friday 2 January 2015

DNS Cache busting

DNS Cache busting is a very simple attack against a caching DNS server. All you need is a domain which is confiured to answer for a wild card (Example: *.domain.com,asd.domain.com etc.).
This attack is being used in the wild.

UPDATE: ISC has since introduced some features to bind to mitigate this attack.

https://kb.isc.org/article/AA-01178/0/Recursive-Client-Rate-limiting-in-BIND-9.9-Subscription-Version.html

fetches-per-zone The maximum number of simultaneous iterative queries to any one domain that the server will permit before blocking new queries for data in or beneath that zone. This value should reflect how many fetches would normally be sent to any one zone in the time it would take to resolve them. It should be smaller than recursive-clients. When many clients simultaneously query for the same name and type, the clients will all be attached to the same fetch, up to the max-clients-per-query limit, and only one iterative query will be sent. However, when clients are simultaneously querying for different names or types, multiple queries will be sent and max-clients-per-query is not effective as a limit.

Apple Pay...Just another way to use a credit card

Is Apple pay really that revolutionary? What does this mean for the world of crypto-currency?
My opinion is that Apple Pay doesn't address any of the features delivered by Bitcoin (and similar altcoins). For example, the decentralized ledger which automates accounting or the ability to transfer funds anywhere in the world with limited infrastructure. The list goes on. Apply Pay just another way to use a credit card in a brick and motar market.