Vulnerability Note VU#552136

Apple Mac OS X UFS filesystem integer overflow vulnerability

Original Release date: 16 Jan 2007 | Last revised: 13 Mar 2007


There is an integer overflow in the ffs_mountfs() function, which is used by Apple's OS X operating system to handle UFS disc images.


Unix File System (UFS) is a file system used by Unix and other similar operating systems. Apple OS X supports UFS, partitions, and images.

There is an integer overflow error in the ffs_mountfs() function that may occur when an OS X system opens a UFS disc image. To trigger the overflow, an attacker would need to convince a user to open a specially crafted disc image. Note that the Safari web browser's default settings consider UFS disc images to be a safe file type, and will automatically open them after downloading.


A remote, unauthenticated attacker with the ability to supply a specially crafted DMG file may be able to cause an affected system to crash, thereby creating a denial of service. The original reporter states that an attacker may also be able to execute arbitrary code using this vulnerability. However, this has not been confirmed.


Apple has issued an upgrade to address this issue. See Apple Security Update 2007-003 for more details.

Disable "Open 'safe' files after downloading"

Disable the option "Open 'safe' files after downloading," as specified in the Securing Your Web Browser document. This will help prevent automatic exploitation of this and other vulnerabilities.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Apple Computer, Inc.Affected-13 Mar 2007
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



This issue was reported by LMH on the month of Apple bugs website.

This document was written by Ryan Giobbi.

Other Information

  • CVE IDs: CVE-2006-5679
  • Date Public: 10 Jan 2007
  • Date First Published: 16 Jan 2007
  • Date Last Updated: 13 Mar 2007
  • Severity Metric: 1.14
  • Document Revision: 19


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