Attackers Targeting Zero-Day Access Flaw

By Lisa Vaas  |  Posted 2007-12-13 Print this article Print

Merely opening a rigged Microsoft Office Access database file is enough to trigger a system takeover.

Attackers are going after Microsoft Office Access databases, US-CERT warned earlier in the week, taking advantage of an unpatched stack buffer overflow to deliver malicious databases that are leading to system hijacking in an undetermined number of cases.

Security researchers didn't have many details on the attacks, but US-CERT's advisory did say that users don't have to do anything beyond open a rigged Access database in order for a successful exploit to be sprung on them. The malicious files are of file type .MDB.
McAfee's Avert Labs said in a Dec. 12 posting that attacks could come via a number of vectors: via the Web, e-mail or instant messaging, "coupled with well-establishing social engineering techniques" to trick victims into launching an attachment that's been booby trapped.
US-CERT is recommending that, in lieu of a patch, users take these mitigation steps:
  • Avoid opening attachments from people they don't know or trust or that they haven't solicited.
  • Block high-risk file attachments at e-mail gateways.
Microsoft Director of Security Response Mark Miller said in a statement that, "Microsoft is aware of public reports of a malicious Microsoft Access Database file being used to compromise users," though he didn't provide information on how widespread the attack is at this point. The file type in question—.MDB—is considered unsafe, Miller noted, since it's one of multiple file types that allow embedded script operations. Macros in Word files (*.doc) or in Excel files (*.xls) are other examples of file types that can be risky because of their less-than-obvious leniency on embedded scripts, according to this Microsoft support page on unsafe file types. .MDB was used by Access Database versions up until 2003 and is either blocked by some Microsoft applications or provokes warnings before users can open such files, Miller said in his statement. Check out's Security Center for the latest security news, reviews and analysis. And for insights on security coverage around the Web, take a look at eWEEK's Security Watch blog.
Lisa Vaas is News Editor/Operations for and also serves as editor of the Database topic center. Since 1995, she has also been a Webcast news show anchorperson and a reporter covering the IT industry. She has focused on customer relationship management technology, IT salaries and careers, effects of the H1-B visa on the technology workforce, wireless technology, security, and, most recently, databases and the technologies that touch upon them. Her articles have appeared in eWEEK's print edition, on, and in the startup IT magazine PC Connection. Prior to becoming a journalist, Vaas experienced an array of eye-opening careers, including driving a cab in Boston, photographing cranky babies in shopping malls, selling cameras, typography and computer training. She stopped a hair short of finishing an M.A. in English at the University of Massachusetts in Boston. She earned a B.S. in Communications from Emerson College. She runs two open-mic reading series in Boston and currently keeps bees in her home in Mashpee, Mass.

Submit a Comment

Loading Comments...
Manage your Newsletters: Login   Register My Newsletters

Rocket Fuel