The FBI has warned e-tailers to guard against hackers.
An alert on the FBI-run National Infrastructure Protection Centre (NIPC) Web site reads: "Based on FBI investigations and other information, the NIPC has observed that there has recently been an increase in hacker activity specifically targeting US systems associated with e-commerce and other internet-hosted sites".
The attacks were targeted mostly at Windows NT operating systems, although Unix-based OSes have not escaped, the FBI alert warns.
"The hackers are exploiting at least three known system vulnerabilities to gain unauthorized access and download propriety information. Although these vulnerabilities are not new, this recent activity warrants additional attention by system administrators," it states.
In most cases, hacker activity lasted for several months before it was spotted, the FBI adds. It advises all network systems administrators to check systems and apply the relevant software patches. Specific emphasis should be placed on systems related to e-commerce or financial business.
A list of the kind of hacking observed by the agency can be found here. Hacking incidents can be reported to www.nipc.gov/incident/cirr.htm. ®