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Original URL: http://www.theregister.co.uk/2008/05/15/apple_safari_carpet_bombing_vuln/

Apple okay with Safari 'carpet bombing' vuln for now

By Dan Goodin in San Francisco
Published Thursday 15th May 2008 19:23 GMT

Next time you get nagged to install Apple's Safari browser keep this in mind: The company's security team has dismissed research that shows a simple way miscreants can use the browser to litter an end user's machine with malicious files.

According to researcher Nitesh Dhanjani, Safari doesn't bother to ask for user permission before downloading resources (http://www.dhanjani.com/archives/2008/05/safari_carpet_bomb.html) from websites. When encountering malicious iframes and other scripts, the browser obediently does what the website tells it to do, including downloading a file as many times as html scripts order.

When informed of this "carpet bombing" vulnerability (as researcher Billy (BK) Rios has dubbed it), Apple agreed that it might be good if Safari actually checked with the user before downloading potentially vicious files, but signaled that kind of addition wasn't much of a priority.

"Please note that we are not treating this as a security issue, but a further measure to raise the bar against unwanted downloads," someone from Apple's security team told Dhanjani. "We want to set your expectations that this could take quite a while, if it ever gets incorporated."

This is unfortunate because the vulnerability allows miscreants to dump hundreds of malicious files into a user's default download location (in Windows it's the desktop and in OS X it's the download folder). As Nate McFeters at the Zero Day Blog sees it (http://blogs.zdnet.com/security/?p=1111), it wouldn't be hard for a rogue site to load up a desktop with dozens of booby-trapped "My Computer" icons that look like the real Windows icon and wait for a confused user to accidentally click on them.

Apple has recently taken lumps (http://www.theregister.co.uk/2008/05/02/safari_share_triples/) because it uses its security update mechanism as a way to push Safari on users who have never installed the browser. This shameless pimping offends the sensibilities of many who believe security update notices should be reserved only for buggy software that presents a clear and present danger - that is for buggy software that's already installed.

We asked Apple to comment, but as of time of publication, they didn't respond. So, we've lit a candle in their honor.

Dhanjani said he discovered a separate, high-risk vulnerability that can be used to remotely steal local files from the user's hard drive, and the company has acknowledged the bug and promised to fix it.

Dhanjani's research comes on the heels of a separate report (http://aviv.raffon.net/2008/05/14/InternetExplorerQuotPrintTableOfLinksquotCrossZoneScriptingVulnerability.aspx) from Aviv Raff that points out a vulnerability in IE 7 and IE 8 that could allow an attacker to remotely execute malicious code on an end user's machine. The fault lies within the "Print Table as Links" feature, which expands the options users have for printing web-related text.

A Microsoft spokesman says company researchers are looking in to the report, but that on the surface exploitation would require "significant" user interaction. Specifically, the victim would have to select non-default printing options and then print a malicious page. Indeed, Secunia rates (http://secunia.com/advisories/30141/) the vulnerability "less critical," its second-lowest rating on a five-notch scale. ®

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