Even data from defunct online accounts can be exposed if it is not properly maintained and secured.
Twitter sent a mass email to Vine account holders on Friday, warning them that their email addresses and phone numbers may have been leaked.
Vine was Twitter’s 6-second video platform, shut down at the end of last year.
A bug affecting the Vine Archive was fixed in less than 24 hours, according to the company, but it could have exposed email addresses and phone number details associated with Vine accounts to potentially malicious third parties.
“In our investigation, we discovered that the email address and phone number linked to your account were exposed,” wrote Vine Support in an email to account holders. “We want to emphasize that this information can't directly be used to access your account, and we have no information indicating that it has been misused. We take these incidents very seriously, and we're sorry this occurred.”
Considering the very real threat of phishing, Twitter recommends that users should be wary of any emails or texts from unknown senders.
The company also emphasizes that it will never send email attachments or request passwords by email. It will only send Vine-related communication from a twitter.com domain name.