Facebook Is Allowing Ad Targeting Based on Contact Information You Have No Control Over:
Even for Facebook's low standards, this is exceptionally unethical: you haven't given them permission to use this information; someone you know or someone you purchased products from has done that for you, probably with consent buried in an opaque privacy policy. There's no way to opt out. And there are few-to-no regulations governing this.
(Via Pixel Envy)
This is a disaster from the security perspective. Users should enable 2FA to protect themselves with an expectation that this data is restricted for only this use.
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