WORM_KELIHOS.CDS
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Worm
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Propagates via email
This malware sends out spam e-mails with malicious links where other malware can be downloaded.
This worm may be downloaded from remote sites by other malware.
TECHNICAL DETAILS
UDP port 53 (Domain Name Server), TCP Port 80 (HTTP)
651,264 bytes
EXE
Yes
10 Apr 2011
Compromises system security
Arrival Details
This worm may be downloaded from remote site(s) by the following malware:
- TROJ_KELIHOS.SMA
It may be downloaded from the following remote sites:
- http://{BLOCKED}r.com/client1.exe
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
SmartIndex = "{malware path and file name}.exe"
Other System Modifications
This worm adds the following registry keys:
HKEY_CURRENT_USER\Software\Google
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Google
ID = 50
HKEY_CURRENT_USER\Software\Google
ID2 = {random values}
HKEY_CURRENT_USER\Software\Google
ID3 = {random values}
HKEY_CURRENT_USER\Software\Google
AppID = "{random characters}"
It creates the following registry entry(ies) to bypass Windows Firewall:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\AuthorizedApplications\List
{malware path and file name}.exe = "{malware path and file name}.exe:*:Enabled:Promo"
NOTES:
It adds the following registry entries to allow connections to TCP port 80 and UDP port 53.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess
\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
80:TCP="80:TCP:*:Enabled:Promo"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess
\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
53:UDP="53:UDP:*:Enabled:Promo"
It sends out spam e-mails which contain links to TROJ_KELIHOS.SMA. This Trojan, in turn, downloads WORM_KELIHOS.CDS. Note, however, that the binaries downloaded from the link may change depending on what infected machine they are retrieved, which changes.
It sends a GET request to the server to download an encrypted data, which contains information on its spamming routine.
The email it sends has the following format:From: {name of sender}
Subject: {subject}
Message Body:
{name of sender} {message 1}
{message 2}
{message 3}
{malicious link}
- {Name of sender}:
- Abraham
- Adalbert
- Baldwin
- Barbara
- Candida
- Carol
- Daniel
- Dannie
- Eddie
- Edgar
- Fanny
- Felicia
- Gabriel
- Geffrey
- Hadrian
- Hannah
- Irene
- Isaac
- Jacob
- James
- Katharine
- Kathleen
- Lambert
- Laura
- Mabel
- Madeleine
- Nance
- Nancy
- Odette
- Olive
- Paddy
- Patricia
- Rachel
- Ralph
- Sadie
- Sally
- Teddy
- Terry
- Valentine
- Veronica
- Wallace
- Walter
- {subject}I made an Ecard for U!
- just mailed to you
- wants to show you
- has created for you
- a postcard.
- an ecard.
- a digital postcard.
- an Online greeting card.
- Click on the link below to see your greeting card:
- Collect your E-card here:
- It is waiting for you at our card site, go ahead and see it! To pick up your greeting card, click on the following link at anytime within the next 30 days:
- To view the ecard simply click the link below:
{malicious link} can be any link where TROJ_KELIHOS.SMA can be downloaded.
It communicates via a peer-to-peer (P2P) mechanism by connecting to other computers infected with this malware through TCP port 80. This type of communication is usually referred to as HTTP2P. It then gets the list of IP addresses the remote computer has logged and adds them to the list of IP addresses it connects to.
It sends list of IP addresses of infected systems once it receives a remote connection via TCP port 80.
SOLUTION
8.900
7.966.06
11 Apr 2011
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 3
Identify and terminate files detected as WORM_KELIHOS.CDS
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
Step 4
Delete this registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- SmartIndex="{malware path and file name}.exe"
- SmartIndex="{malware path and file name}.exe"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\AuthorizedApplications\List
- {malware path and file name}.exe="{malware path and file name}.exe:*:Enabled:Promo"
- {malware path and file name}.exe="{malware path and file name}.exe:*:Enabled:Promo"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
- 80:TCP="80:TCP:*:Enabled:Promo"
- 80:TCP="80:TCP:*:Enabled:Promo"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
- 53:UDP="53:UDP:*:Enabled:Promo"
- 53:UDP="53:UDP:*:Enabled:Promo"
Step 5
Delete this registry key
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_CURRENT_USER\Software
- Google
- Google
Step 6
Scan your computer with your Trend Micro product to delete files detected as WORM_KELIHOS.CDS. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
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