RSA chairman Art Coviello has offered to replace customers' SecurID tokens after admitting that the security technology has been compromised.
Coviello said in an open letter that an investigation into the attack on Lockheed Martin's servers had found evidence that the hackers had used information gleaned from a March attack on RSA's own databases.
RSA is offering to replace SecurID tokens for customers concerned with corporate networks and protecting intellectual property, which is potentially all 40 million token users.
The company will also offer risk-assessment software which monitors for unusual patterns of user behaviour.
"We remain highly confident in the RSA SecurID product as the leading multi-factor authentication solution, and we also feel strongly that the specific remediations we have provided to customers will help to deliver the highest levels of customer protection," said Coviello.
"However, we recognise that the increasing frequency and sophistication of cyber attacks generally, and the recent announcements by Lockheed Martin, may reduce some customers' overall risk tolerance."
The SecurID system uses a token which generates a six-digit passcode every 30 or 60 seconds, to be used alongside the standard username and password for logging in.
The basis for the code generation are so-called seed numbers, on which the system depends to generate the right set of digits.
Coviello did not give any more details about the attack, but experts have speculated that a proportion of, or possibly all, the seed numbers were stolen.
Each token is built around a specific seed number, but needs to be matched to the user's token, and this could be how Lockheed Martin blocked the attack.
Given the nature of Lockheed Martin's work, and the fact that this was the only case RSA had come across, Coviello said that the attackers were most likely involved in espionage, rather than seeking financial gain or "public embarrassment".
The company is prioritising military and government systems for replacement and remediation.
Nevertheless, the admission will cause an immediate knock to RSA's reputation in the security industry, and the replacement process will take time and money.
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