Twitter has warned its 330 million users to change their passwords after a glitch exposed some in plain text on its internal network.

The social network said an internal investigation had found no indication passwords were stolen or misused by insiders.

However, it still urged all users to consider changing their passwords “out of an abundance of caution”.
http://www.bbc.com/news/business-43995168

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Twitter Urges Users to Change Passwords Due to Glitch
Twitter said Thursday that a glitch caused account passwords to be stored in plain text on an internal log, sending users across the platform scrambling to change their passwords.

The social media company said that it found and has fixed the glitch, and its investigation shows no indication of a breach or misuse by anyone. While the company did not specify how many passwords were impacted, a Reuters report pegged the number at more than 330 million.
https://threatpost.com/twitter-urges-users-to-change-passwords-due-to-glitch/131693/

Twitter urges users to change their passwords after discovering a bug that revealed them internally
Twitter on Thursday encouraged its more than 330 million users to change their passwords after the company discovered a bug that revealed the passwords in an unencrypted form in an internal log.

Twitter said in a blog post that “we have no reason to believe password information ever left Twitter’s systems or was misused by anyone.” But the company urged users to take action “out of an abundance of caution.”
https://www.washingtonpost.com/news/the-switch/wp/2018/05/03/twitter-urges-users-to-change-their-passwords-after-discovering-a-bug-that-revealed-them-internally/