The Scottrade data breach affects 4.6 million accounts

The breach was discovered by federal authorities, not the company itself

Retail brokerage firm Scottrade has announced that it has been the victim of a major data breach.

The company was informed of the disaster by federal law enforcement officials. Scottrade was previously unaware that the breach had taken place until that point.

Interlopers were apparently active on the organization's network around the end of 2013 going into early 2014, and details from no less than 4.6 million user accounts were accessed, Engadget reports.

The attackers were able to glean contact details from the system they hacked into, although apparently this system also contained more sensitive data such as Social Security numbers.

No fraudulent activity

In a "cybersecurity update," Scottrade attempted to reassure customers that financial data wasn't touched: "We have no reason to believe that Scottrade's trading platforms or any client funds were compromised. Client passwords remained fully encrypted at all times and we have not seen any indication of fraudulent activity as a result of this incident."

Those 4.6 million clients who have been affected by the breach are being contacted by the company, and also offered identity protection services.

Scottrade said it had now fully patched up the intrusion point that the attackers exploited, and it was fully cooperating with the authorities currently investigating the matter.

The company also noted that it was carrying out its own internal data forensics investigation in conjunction with a top computer security firm, and that it had already taken steps to bolster its network defenses and lessen the chance of a repeat of this incident.