However, sensitive user data has not been shared with the company’s third-party partners and the issue which stemmed the incident has been taken care of; now the phone numbers and email addresses are only asked for security purposes, according to Twitter.
Last year, Facebook was caught for engaging in a similar practice where the phone numbers and email addresses provided by the users to make their accounts more secure were used by the social media giant to target ads, as per the Federal Trade Commission (FTC).
In the wake of the breach, Twitter received widespread criticism for compromising its users' privacy. The fact that user security has been violated through a framework that was intended to rather strengthen it, further fuelled the public reproval. Although the company did not intend to use sensitive user data for the purpose of ad targeting, one can’t deny that the platform was practicing the aforementioned without the knowledge of its users. Moreover, it took the company almost a month to disclose the information.
Putting what Twitter called as an 'error' into perspective, it wrote in a post on its Help Center website, “Tailored Audiences is a version of an industry-standard product that allows advertisers to target ads to customers based on the advertiser's own marketing lists (e.g., email addresses or phone numbers they have compiled)."
"When an advertiser uploaded their marketing list, we may have matched people on Twitter to their list based on the email or phone number the Twitter account holder provided for safety and security purposes." The company added.
Remarking data (here) as a liability, Duruk, a human-computer interface expert, wrote “Phone numbers stored for 2FA end up in advertising hellhole. The more you accrue, the more someone inside your org will find a way to abuse it.”
Apologizing for the inadvertent mistake, Twitter further wrote, "We’re very sorry this happened and are taking steps to make sure we don’t make a mistake like this again."
