The Privacy Theater of Hashed PII
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The Privacy Theater of Hashed PII
1–10 of 28 posts
Re: The Privacy Theater of Hashed PII
#2Isn't this solved with salt?
Re: The Privacy Theater of Hashed PII
#3Isn't this solved with salt?
If it's salted, you can't share it with a third-party and determine who your customers in common are. (That's the point of the salt; to mean that my_hash(X) != your_hash(X)).
Re: The Privacy Theater of Hashed PII
#4The company I work for has a similar, yet even worse instance of this. The employee satisfaction survey was advertised as anonymous, but when I looked into the implementation they were just hashing the email address, of which there were only a few thousand. A more conspiratorial mind would conclude that it is to easily be able to find who a particular piece of feedback came from, but in this case I legitimately think it's just incompetence and not being able to figure out a better way of ensuring each employee can only submit the survey once.
This year it's advertised as confidential, rather than anonymous, so I suppose that is an improvement.
Re: The Privacy Theater of Hashed PII
#5Re: The Privacy Theater of Hashed PII
#6Isn't this solved with salt?
> A 2020 MacBook Air can hash every North American phone number in four hours
If you added a salt, this would still allow you to reverse some particular hashed phone number in about 4 hours, it just wouldn't allow you to do all of them at the same time.
Re: The Privacy Theater of Hashed PII
#7It is mostly performative. They do it so nobody can point fingers and accuse them of not doing it.
Re: The Privacy Theater of Hashed PII
#8"Can we just hash the IP addresses?"
Re: The Privacy Theater of Hashed PII
#9This is not for privacy. It is done for the sellers/buyers of PII, buyers do not want to buy data they already own and the seller doesn't want to disclose data before they sell it.
There is no honour amongst data thieves.
Re: The Privacy Theater of Hashed PII
#10Isn't this solved with salt?
A salt is very good if the input varies. If the input stays within a pre-defined range (e.g. phone numbers), salt does not work very well.