The United States Industrial Control Systems Cyber Emergency Response Team (ICS-CERT) has issued a warning about an active "spear phishing" campaign targeting companies in the natural gas pipeline sector.
In an advisory issued last week, ICS-CERT said it has received information about targeted attacks and intrusions into multiple organizations over the past several months.
The attacks are related to a single campaign and appear to have started in late December 2011, the advisory noted. "Analysis shows that the spear-phishing attempts have targeted a variety of personnel within these organizations; however, the number of persons targeted appears to be tightly focused," the ICS-CERT said.
"In addition, the e-mails have been convincingly crafted to appear as though they were sent from a trusted member internal to the organization," it said.
ICS-CERT is currently working with multiple organizations to determine the scope of the attack activity and to discuss mitigation measures. It has also conducted a series f briefings with infrastructure asset owners around the country to share information on the attacks, the advisory noted.
The Christian Science Monitor, which was the first to report the attacks, quoted unidentified sources as saying that the U.S. Department of Homeland Security (DHS) has so far released at least three confidential "amber" alerts warning gas pipeline companies about the attacks.
The DHS alerts were far more specific than the ICS-CERT advisory and contained details like file names, IP addresses and other markers that a company could use to see if it was breached, The Monitor said in its report.
Interestingly, one of the alerts asked companies that believed they had been breached, not to do anything to stop the malicious activity on their networks The Monitor said, quoting an individual who claimed to have seen the alert.
The goal apparently is to gather as much information on the attacks as possible without tipping the attackers that they had been discovered, the report said.
Patrick Miller, principal investigator of the National Electric Sector Cybersecurity Organization, said that the wording in the alerts suggest that at least some organizations may have been breached. "We haven't seen any raw breach data, but it is implied based on what we have noticed [in the alerts]," he said. "We do have indicators that the threat is active."
News of the ongoing so-called spear phishing attempts is sure to focus attention on the ability of U.S. critical infrastructure organizations to withstand targeted and persistent attacks.
Even so, an organization's ability to defend itself against such attacks rests substantially on its employees.
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