Stepping up its criticism of a planned domain-name expansion, marketers are asking the U.S. Department of Commerce to seek an independent probe of a recent security breach at the Internet Corporation for Assigned Names and Numbers. "The marketing and Internet communities are concerned about ICANN's vulnerability," Association of National Advertisers president and CEO Bob Liodice said Wednesday in a letter to Lawrence Strickling, assistant secretary for communications and information at the Department of Commerce. The letter calls for the Commerce Department to "use all efforts possible" to ensure that ICANN arranges for outside experts to review the data breach. The security glitch came to light two weeks ago, when ICANN said it had learned that some applicants for new top-level domains could see other applicants' information. ICANN said it had temporarily stopped accepting applications for new top-level domains -- the last portion of a URL, like ".com" or ".edu." The organization says it expects to resume accepting applications by Friday. The Association of National Advertisers contends that the security glitch calls into question whether ICANN can prevent fraudsters from registering brand names they don't own in order to dupe consumers into purchasing counterfeit merchandise or revealing sensitive financial information. "This incident could indicate that ICANN might be rushing to meet artificial deadlines of its own creation, resulting in inevitable system errors," the ANA says in its letter to Strickling. The marketing association also asked Strickling to support the ANA's calls for a "do not sell" list that will allow companies to prevent their brand name from being used as a domain by anyone else. "It is our belief that some of the challenges ICANN is encountering with the TLD application process -- apart from the security vulnerability -- such as dealing with an enormous number of applications ... could be alleviated by our proposal," the letter states. In January, ICANN went ahead with an initiative to allow any word -- including brand names -- to serve as a generic top-level domain. Between Jan. 12 and March 25, the group received applications for 839 top-level domain names. Currently, there are only 22 generic top-level domains. It's not yet known how many of those applications will be approved, but the ANA says that a significant increase could result in sites run by counterfeiters or other scammers. ICANN has said it has procedures aimed at preventing cybersquatting or trademark infringement. In addition, acquiring a new top-level domain will cost at least $185,000 -- which some observers say is high enough to discourage illegitimate registrations.