Citrix customers using the firm's GoToMyPC tool will have to change their passwords after the service was hit by a "very sophisticated attack".
Citrix has issued a report on the incident and apologised to customers for falling victim to the hack.
"Dear valued customer, unfortunately, the GoToMyPC service has been targeted by a very sophisticated password attack. To protect you, the security team recommend that we reset all customer passwords immediately," said Citrix in an incident report.
"Effective immediately, you will be required to reset your GoToMyPC password before you can log-in again. To reset your password please use your regular GoToMyPC log-in link," explained Citrix.
Once there you should choose a password carefully, and consider adopting the company's two-factor authentication service.
It's all good advice, and nothing we have not seen before. The short version is to use something long, complex and comprising a mix of numbers and characters. The really short version is don't use 'Passw0rd'.
"When resetting your password we highly recommend using a new password and not the same one the account was set to previously, if possible," Citrix added.
"In addition we would like to remind all users that GoToMyPC offers two-step verification, an additional preference which can further enhance the security of your account."
The incident is just the latest in an almost endless series of hacks and data breaches that have hit companies including LinkedIn and Myspace, which in turn led to hacks of major celebrities' Twitter accounts, including Mark Zuckerberg's.
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