The issue has been rectified as of September 17.
In yet another instance that highlights the growing breach of privacy by social media sites, Twitter Inc has disclosed that email addresses and phone numbers uploaded by users “to meet security requirements may have been ‘inadvertently’ used for advertising purposes”.
The issue was rectified by September 17.
Twitter did not disclose how many users were affected by the inadvertent mistake.
“This was an error and we apologize,” said Twitter in a blog post.
The development comes in the wake of social media companies, including Facebook, and Twitter facing heat from regulators and users over how user-data is handled on their platforms.
In a statement Twitter said, when advertisers uploaded their marketing lists, it may have matched people on the platform to their list based on the email or phone number provided by account holders.
It went on to add, although the information was not shared with third parties, however, it was made available internally to allow users to receive targeted advertising.