Reddit has reset 100,000 passwords after hackers stole people's credentials from other sites to take over their accounts.
The social network alerted its user base yesterday to the fact it had sent out the reset notices over the past fortnight, following hacks on sites such as LinkedIn, which spilled 117 million people's account details back in 2012, which a hacker decided to sell for 1,500 this month.
"With this access to likely username and password combinations, we've noticed a general uptick in account takeovers (ATOs) by malicious (or at best spammy) third parties," a post by Reddit read.
Explaining that Reddit has not been hacked, the firm said the rise in account takeovers was down to people re-using the same passwords on multiple sites, meaning hackers with their LinkedIn credentials could use the same details to log into their Reddit accounts.
"We've ramped up our ability to detect the takeovers, and sent out 100k password resets in the last 2 weeks," Reddit added. "More are to come as we continue to verify and validate that no one except for you is using your account."
It advised people to use "strong, unique" passwords, setting and verifying email addresses for their account, and checking their account activity for unusual goings-on.
LinkedIn suffered the data breach in 2012, but only realised earlier this month that hackers were selling the data online it said people's accounts still at risk were those who had not changed the password in the aftermath of the cyber attack.
In an email to its 400 million members sent this week, LinkedIn explained other measures it has taken to mitigate the breach.
It said: "We invalidated passwords of all LinkedIn accounts created prior to the 2012 breach that had not reset their passwords since that breach.
"In addition, we are using automated tools to attempt to identify and block any suspicious activity that might occur on LinkedIn accounts. We are also actively engaging with law enforcement authorities."
The consequences of the LinkedIn hack led Microsoft to pledge to ban simple, overused passwords in order to improve security.
In a blog post, Microsoft's identity division director, Alex Simons explained his team analysed common passwords so Microsoft users are blocked from picking them.
Various missions are underway to improve security, such as Google and Yahoo both trying to replace passwords with other methods for people to identify themselves.
