n.runs-SA-2009.006 - Apple Safari - Null pointer dereference
Vendor: Apple Inc., http://www.apple.com
Affected Products: Safari Browser 3.2.3 all platforms
Vulnerability: Null pointer dereference lead to DoS
2009/06/07 Bug found
2009/06/08 Preparing PoCs and problem description for three bug
classes (n.runs-SA-2009.004 - n.runs-SA-2009.006);
writing initial email
2009/06/08 Apple releases Safari 4.0 
2009/06/09 Sending initial email in midnight hour (UTC/GMT +2 hours)
2009/06/09 Bot reply mail delivered; received Follow-Up ID
2009/06/09 Due to a press release n.runs is now aware of new release;
testing three PoCs; two of them seems to be fixed
2009/06/10 Apple replies and outlining "to take any report of a
potential security issue very seriously." Asking for PoCs
2009/06/10 Sending all PoCs with further description and outlining
at the time of writing the initial email, n.runs was aware
of new Safari release. Two PoCs (n.runs-SA-2009.005 and
n.runs-SA-2009.006) are not working with new Safari
release but asking to have a closer look into it.
2009/06/11 Apple response two PoCs are not working on the latest
release, so Apple dont see the need for any further
action. With regards to n.runs-SA-2009.004, Apple
acknowledge the issue still affects Safari 4 and is
looking to fix it.
2009/06/15 n.runs informs Apple to release this advisory
due to time difference
2009/06/23 n.runs releases this advisory
"What is Safari ?
Its a browser. Its a platform. Its an open invitation to innovate.
Whether on a Mac, PC, iPhone, or iPod touch, Safari continuously
redefines the browser, providing the most enjoyable way to experience
A Null Class Pointer Dereference in CoreFoundation.dll has been found
while parsing a URL fragment with a high-bit character in a common
In detail, the following flaw was determined:
- Safari crashes in method CFCharacterSetInitInlineBuffer because the
first passed pointer argument (stored in ecx) was not sanized.
Hence dereferencing a null pointer Sarafi will crash.
Excerpt from stack trace:
An attacker could trigger the vulnerability by constructing a specially
prepared website. When a user views the web page an unexpected
application termination occurs.
Kindly note: Whether this circumstance leads to an exploitable condition
was not closer investigated.
Apple has issued an update to correct this vulnerability.
For detailed information about the fixes follow the link in
References  section of this document.
Bugs found by Alexios Fakos of n.runs AG.
This Advisory and Upcoming Advisories:
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