Archive
Analysis of OSX Starfield
When you download an application or installer from legitimate website, you establish a level of trust expecting not to be tricked or deceived.
Distribution:
The installer is distributed by Starfield a technology and research branch of Go Daddy Group. If you are Go Daddy user, when you logged-in, this tool is available in the tool section as:
1) Desktop Notified Installer
2) It is also offered as “Web-Based Email Tools plugin” promising that this tool will enable image paste.

It’s possible that this installer will be distributed elsewhere.

When you download the installer, you’ll notice two things:
1) It is telling you “Double-click to Install”
2) It is not the installer itself, instead it is a shortcut link.
Why?
It is a social engineering trick. It attempts to trigger user’s immediate impulse to respond based from a command or instruction.
total 8
Installation: What happens when you ‘double click’ it? You’ll notice that it requires root privilege.
In this stage, it is already too late because even if you decide to discard or cancel the authorization, the tricky ‘StarfieldInstall.app’ has already installed itself as follows:
1) It creates a ‘Starfield’ folder in the Application directory. In this folder, you’ll find a copy of itself and an update component.
/Application/Starfield/StarfieldInstall.app
/Application/Starfield/starfieldupdate.app
2) It is set to run at login by adding ‘starfieldupdate’ in the Login Items.
3) It is always running in the background.
So, when you thought it’s gone, it’s not because ‘StarfieldInstall’ sleeps and activates again to request your password. It will continue to annoy you with repeated request until it gets authorized.
- OS version and CPU Type
- Local user
- Previous installation
- Starfield installation component versions
And performs the following:
- Checks user privilege on the system by checking if user is admin or if the user can be elevated to admin.
- StarfieldInstall launches ‘starfieldupdate.app’ which is kept in the background.
- ‘starfieldupdate.app’ is responsible for initial installation (first run) and updates.
- The initial installation path of Starfield would be:
- Dumps data log of its activity especially the installation. Notice the name ‘starfield’ in the ~/Library/Logs/ folder.
Payload:
The payload is mainly handled by ‘StarfieldInstall.app’. When the user inputs the password, the installation continues by sending a HTTP request to the server as follows:
‘Moduleinfo’ is a JSON text which ‘StarfieldInstall.app’ parses and evaluating the content of a JSON string. For example, it reads and evaluate which package appropriate to the user: Windows or Mac.
{ "win" :
…
, "mac" :
It also evaluates the installation requirement, example:
‘StarfieldInstall’ compares this requirement defined by JSON file ‘moduleinfo’ before it downloads, extracts and run the latest package resulting to installation of the following:
starfieldinstall.zip
starfieldupdate.zip
fileedittool64.plugin.zip
fileedittool.zip
WBETools14.plugin
wbetools64.zip
copypaste.xpi
zoomext.xpi
offdavhelper_mac4.zip
offdavhelper_mac.zip
offsettings.bundle.zip
wbesettings.bundle.zip
drivemapreconnect.zip
backupstatus.zip
offsync_mac.zip
desktoptools.zip
wbedesktopnotifier.zip
So far we have 17 files here and 4 of these files do not require root password. It is important to take note that ’StarfieldUpdate.app’ is always running in the background and launch ‘StarfieldInstall.app’ to perform the following:
- Evaluating JSON text ‘moduleinfo’ for update
- Download and installation of latest versions
- Discovery of products installed
- Running privileged shell command
It installs two Firefox extensions and plugins, which is persistent. It means that you can’t just click ‘uninstall’ to remove it . In Firefox, click Tools and Addons to view the installed Extensions and Plugins as shown below:
Another notable process created is ‘OffSyncService’ which is always running in the background .
In conclusion, this is a nasty and abusive application that performs remote activities and installation of unwanted plugins and application without user consent. It is a bloatware and a backdoor.
Bandwagon effect
Google.com/trends allows you to check some popular searches or trends that threats might take advantage as well.
However, you don’t often check it, and for events like “Station Fire” which I just learned from the news this morning (here in Melbourne), it’s good that there are concern Mac users that sends you a heads up!
As a result, I’ve published this post.
Latest Threat: MacCinema
MacCinema is the latest OS X threat. It’s not really new, it is an update of MacAccess although this time it uses different strings and clever obfuscation but overall the installation and behavior remains the same.

So, here’s the fixed one…
This will output script below…
Notice the IP Address “213.163.64.78″- This is the backdoor IP which executed through cronjob. The backdoor is responsible for executing or installing “DNSChanger” which will change or add malicious DNS entries : 85.255.112.81, es : 85.255.112.114
Notice “enialbdivad 777 nigeb”, obviously we have to fix again …. 
To fill up our curiosity, here’s the final deobfuscated script.

To remove this threat, just follow MacAccess removal instruction.
Malicious CHM
I was cleaning up my messy folders when I bumped on this file – chungtak.chm. I reckon, it was the malicious CHM file spreading around early March of this year.
Is this another exploited file ? Let’s take a look …
CHM Basic File Structure
Microsoft’s HTML Help CHM format starts with 38 bytes of header information and then followed by header sections which contains information such as total filesize and directory list.
This header is followed by directory chunks which consist of index and listing chunks.
The content is self explanatory while the section data is actually part of the content which associates other related files. The section data could contain compressed or uncompressed data. The compressed section uses LZX compression method, which is popularly used in Microsoft cabinet files.
[Read Matthew T. Russotto CHM file format]
With this basic information, let’s investigate the suspicious file – chungtak.chm.
1 – Chungtak.chm
2 – Using CHM decoder tool, these files were extracted.
3 – Chungtak.chm main page is Index.htm. Index.htm contains a malicious code that allows music.exe to execute.
4 – music.exe is a Trojan Dropper. A good analysis posted in McAfee Avert Labs Blog last March 11.
So, what happened? The CHM file is not exploited instead the malicious user uses a legitimate feature that allows an external local file execute by linking it to the chm. [Read CHM Linking Tips]
Analysis of SWF Exploit
With recent massive websites carrying SWF exploit, it’s impressive to see thorough analysis from fellow collegues.
Zarestel’s SWF Exploit analysis on series:
SWF Exploit – CVE-2007-0071 Part 1
SWF Exploit – CVE-2007-0071 Part 2
AusCERT 2008: Telstra Distributed Infected USB
Telstra is red-faced after handing out malware-infected USB drives to tutorial attendees at the AusCERT security conference on the Gold Coast. [Read Patrick Gray @ SearchSecurity]
Virus Total returned 96.88% detection rate which is 31/32 different AntiVirus scanners detect this malware. [VirusTotal Detection]
The culprit … As you can see in the screenshot below, autorun.inf contains instructions that allows USB to auto play once it is mounted in the computer and thereafter, automatically execute sys.exe.
McAfee detects this malware as W32/CEP.worm!33925d66 and has already published a malware report found here.
ThreatExpert Report here.
Archived Malware Reports
It feels good when your old malware reports still exist. I’m saying this because there was once a ruling (Trend Micro AV guidelines) that the last one who analyzed and modified the report gets the credit. So, the original analyst name is removed. I think they already modified this rule …
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=PE_CORN.A
http://www.trendmicro.com/vinfo/jokes/jokesDetails.asp?JNAME=JOKE%5FPCHAUNT%2EA
http://www.trendmicro.com/vinfo/de/virusencyclo/default5.asp?VName=REG%5FZIKDOW%2EA
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=REG_ZIKDOW.A&VSect=T
http://www.trendmicro.com/vinfo/grayware/ve_graywareDetails.asp?GNAME=ADW%5FBARGBUDDY%2EA
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=BKDR_DAEMONIZE.A&VSect=T
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=WORM_ALPHX.A&VSect=T
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=HTML%5FALPHX%2EA&VSect=T
I remember this, the detection name was named after my sister – Minehaha.
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=BKDR_MINEH.A&VSect=T
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=IRC%5FMINEH%2EA&VSect=T
I can’t find my name anymore… TROJ_THEMS — Meths. Actually, the rule is if its new and nobody detects it, then the analyst can name it (of course, following the naming conventions and guidelines).
Speaking of malware naming conventions, this topic is currently a who lot confusion to the industry… few AVs follow CARO naming scheme while others have their own.
Another thing is ethical issue, usually everyone gives the credit of following the detection name if someone already created the detection for that malware (given the name is right – meaning it is readable and doesn’t have any conflicts to a person, company and etc..) but some AV doesn’t follow instead they create their own name (perhaps, for marketing and PR/media purposes).
Refer this recent list/update from AVTest.org:
2008-05-12 Cross Reference List of Virus Names
Each vendor of anti-virus software has a different naming convention and the same virus could have a completely different name in another company’s product. To provide a candle in the dark and diminish the current confusion we created a cross-reference list of all virus names (421 KB), based on the WildList 03/2008










Recent Comments