By Lisa Vaas
October 2, 2007
All iPhone applications run with full root privileges and any
application vulnerability means winner takes all.
The iPhone has been turned into a "pocket-sized network-enabled root
shell," said H.D. Moore, thanks to the well-known security researcher
having published shell code for the smart phone and instructions on how
to use it as a portable hacking platform.
Because of his work, Moore's highly popular Metasploit Framework
penetration-testing tool can now be used to easily write point-and-click
exploits targeting iPhone application vulnerabilitiesexploits that will
give an attacker complete control of the device, given that all of the
phone's applications run with root access.
Moore on Sept. 25 published details of his recent work on the iPhone.
Besides publishing shell code, Moore revealed multiple security chasms
on Apple's device: The first and most shocking is that each and every
process running on the iPhonefrom the mobile version of Apple's Safari
browser to its mail client and even the phone's calculatorall run with
full root privileges. What that means: A security vulnerability in any
iPhone application can lead to complete system takeover.
"A rootkit takes on a whole new meaning when the attacker has access to
the camera, microphone, contact list and phone hardware. Couple this
with 'always-on' Internet access over EDGE and you have a perfect spying
device," Moore said.
Others agree. "The shellcode combined with the number of bugs present in
the iPhone finally make mobile attacks a real threat," wrote Errata
Chief Technology Officer David Maynor in a blog posting.
Charlie Miller - a researcher with Baltimore-based Independent Security
Evaluators, and one of a trio who were first to unveil security issues
with the iPhone and release iPhone "vibrate" shellcode at Black Hat
2007told eWEEK in an interview that he wishes he'd been able to use
Metasploit when he was writing exploits for the gadget back in July.
"It will certainly make life easier" for others who write exploit code
for the iPhone, he said. "Metasploit is the go-to point-and-click
[pen-testing] interface. It's really designed to help you write exploits
and deploy [them] in ways anyone can use. Jailbreak [another development
tool] was available [at the time Miller was writing exploits]. But now
[Moore] has Metasploit where you can right away build payloads that run
as executables on the iPhone."
As it is, within three days of the smartphone's July launch hackers
cracked the iPhone's firmware, finding not only that the phone runs on a
Unix-like operating system but going so far as to extract the master
root and other system passwords.
Moore waited until the iPhone price dropped and until the toolchain tool
for iPhone application development was released before he bought an
iPhone to pick apart.
He first installed AppTapp, an iPhone package manager that downloads
applications over Wi-Fi or EDGE. With the installer, he added OpenSSH
- an open-source shell program that provides encrypted communication
using the SSH protocol and a VT-100 Terminal to the phone, and voila
(after a "few headaches," he said), he had shell access.
Moore says he can now generate working iPhone shellcode with a version
of Metasploit 3.
Once he had shell access, he found not only that all applications run
with root access, but an assortment of other things potentially
interesting to malware writers or to any of the many people who love to
One such observation: The iPhone has a potential security pitfall in
that its MobileMail application supports Microsoft Office document
formats by using the OfficeImporter framework when converting files into
viewable form. "This looks like a great target for file-format fuzzing
and some late-night reverse engineering," Moore said.
Another potential way for attackers to get into the phone is through the
mDNSResponder service, which runs by default, Moore said. The
mDNSResponder, used by iTunes for music sharing, is part of the Bonjour
application suite, which provides automatic and transparent
configuration of network devices.
When the iPhone first syncs with iTunes, its host name is changed, Moore
said. The default hostname becomes "User's iPhone," with the Mac OS X
user account name filling in for "User." If the iPhone is connected to a
Wi-Fi network, the mDNS service exposes the iPhone owner's user name.
That particular security exposure hasn't yet responded to Moore's
probes, he said, making active discovery "less likely."
Moore has also been playing with the "vibrate" shellcode released by
Miller at Black Hat 2007. By the time the security show rolled around,
Independent Security Evaluators had already revealed, shortly after the
smart phone's release, that Apple's popular multifunctional device could
be exploited for data theft or snooping purposes.
At the time, Miller, Jake Honoroff and Joshua Mason created an exploit
for the iPhone's Safari Web browser wherein they used an unmodified
device to surf to a maliciously crafted drive-by download site. The site
downloaded exploit code that forced the iPhone to make an outbound
connection to a server controlled by the security firm.
The researchers showed that a compromised device then could be forced to
send out personal data, including SMS text messages, contact
information, call history, voice mail information, passwords, e-mail
messages and browsing history.
Miller told eWEEK that with Moore's Metasploit work, the time needed to
write iPhone exploits has substantially shrunk. "One thing interesting
about the work H.D.'s done, if you look at the time frame, is it took us
two days to find a vulnerability and write something to where we knew it
was legitimate. [It took] seven or eight days after that to having a
working exploit. If we had what H.D. has done, it would have taken maybe
a day or less. Having this available now will cut what we did from two
weeks to two days.
Now that the iPhone has been out for months, is the desire to hack it
still at a fever pitch? Miller said that given how much personal
information an attacker can shake out of the device, "It probably is
something people should worry about."
"[Like H.D. said in his blog,] It's always on, it's always on the
Internet, and you can get a lot of personal information. It's a viable
target," Miller said.
So now it's time for real fun.
"It's going to be such good times," one blogger wrote after Moore
published his findings. "we have the accessibility/vector. What we need
are market saturation (some predict 14M sold by end of 2008,) a mesh
networking application (or something to cross-connect the myriad of
networking options) and an attractive application to encourage the
owners to share amongst each other (say, some funky music sharing
application or social networking tie-in, or instant messaging.) That'll
lay the ground work for some very effective malware."
For his part, Moore said in his posting that he's added support for
iPhone executables to the msfpayload command, allowing users to generate
stand-alone bind/reverse shell executables using a syntax supplied in
his posting. Next up is an XOR encoder, and then all hell should break
"Once the XOR encoder is done, the only step left is to find the bugs
and write the exploits :-)," Moore wrote.
By the time this article posted, Apple had not responded to a request
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