Inference Attacks

Phil Factor explains that your technique for pseudonymizing data doesn’t necessarily anonymize the data:

It is possible to mine data for hidden gems of information by looking at significant patterns of data. Unfortunately, this sometimes means that published datasets can reveal sensitive data when the publisher didn’t intend it, or even when they tried to prevent it by suppressing any part of the data that could enable individuals to be identified

Using creative querying, linking tables in ways that weren’t originally envisaged, as well as using well-known and documented analytical techniques, it’s often possible to infer the values of ‘suppressed’ data from the values provided in other, non-suppressed data. One man’s data mining is another man’s data inference attack.

Read the whole thing.  One big problem with trying to anonymize data is that you don’t know how much the attacker knows.  Especially with outliers or smaller samples, you might be able to glean interesting information with a series of queries.  Even if the application only returns aggregated results for some N, you can often put together a set of queries where you slice the population different ways until you get hidden details on individual.  Phil covers these types of inference attacks.

Related Posts

Aggregations And Always Encrypted

Monica Rathbun finds trouble with Always Encrypted: The real challenges started when the client began to test their application code. The first thing we hit was triggers. The table had several insert triggers associated with the columns that were now encrypted. Since the data was now encrypted the insert triggers would fail. Again, we lucked […]

Read More

Storing Credentials For Containers

Andrew Pruski shows how to store a credential using Powershell and pass it into a Docker container: I work with SQL Server in containers pretty much exclusively when testing code and one of my real bug bears is that SQL Server in containers does not support Windows authentication (unless you’re using Windocks). So when I’m working […]

Read More

Categories

August 2017
MTWTFSS
« Jul Sep »
 123456
78910111213
14151617181920
21222324252627
28293031