Mac OS X flaw: US gov adds warning

US-Cert issues alert...

By Tom Espiner, 27 November 2006 08:50

NEWS

The US government has added its weight to warnings about a vulnerability in Apple Mac OS X.

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The US computer emergency response team (US-Cert) issued an alert last week, reporting a failure in the way OS X handles corrupted disk image files - for Macs, the '.dmg' file format.

A disk image file is a digital representation of the contents and structure of a storage device like a CD or DVD. According to US-Cert, the vulnerability in OS X may allow an attacker using malformed '.dmg' files to corrupt system memory in a way that could allow arbitrary code execution, or cause a denial of service.

The researcher who found the vulnerability claimed it is remotely exploitable as Apple's Safari browser can be set to automatically open '.dmg' files downloaded from external sources. According to the researcher, this can be prevented by changing the browser preferences and deactivating the functionality for opening "safe" files after downloading.

However, the US-Cert vulnerability note said the organisation was "currently unaware of a practical solution to this problem".

Tom Espiner writes for ZDNet UK

Comments

There are 2 comments. Join the discussion

  1. 1. Don Tregartha

    But don't forget the OS requires explicit permission from the root user to install anything in the root directory.

    Now that won't stop somebody with suuficient access rights from putting in their password, but not everyone in the Mac world is THAT daft.

    What won't happen is the OS automatically stuffing malware all over the system.

  2. 2. Steven Fisher

    No, Don, it doesn't. Once code is running as root it's all over for Mac OS X's security model. Unfortunate but true.

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