F-Secure
Tools
Trojan-Downloader:W32/Exchanger.AJ
| Name : | Trojan-Downloader:W32/Exchanger.AJ |
| Detection Names : |
Trojan-Downloader:W32/Exchanger.AJ Trojan-Downloader.Win32.Exchanger.ly Trojan-Downloader:W32/Exchanger.AJ |
| Size: | 78848 |
| Category: | Malware |
| Type: | Trojan-Downloader |
| Platform: | W32 |
Summary
This type of trojan secretly downloads malicious files from a remote server, then installs and executes the files.
Details
Registry Modifications
Sets these values:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\CbEvtSvc
Type = 00000010
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\CbEvtSvc
Start = 00000002
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\CbEvtSvc
ErrorControl = 00000001
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\CbEvtSvc
ImagePath = %SystemRoot%\System32\CbEvtSvc.exe -k netsvcs
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\CbEvtSvc
DisplayName = CbEvtSvc
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\CbEvtSvc\Security
Security = \x01\x00\x14\x80...
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\CbEvtSvc
ObjectName = LocalSystem
Additional Details
This malware is spread via spam e-mails with the title "CNN Alerts". These e-mails are crafted to resemble a real CNN news alert e-mail.
The spam e-mails contain a link or links; in this case, the links are "Usher re-hires mother as manager" and "FULL STORY". When the user clicks these links, a prompt will appear requesting the user to download and execute a file named adobe_flash.exe, which is purported to be necessary to read the full story. The downloadable file is in fact malware. Once the file is downloaded and installed, it then starts as a service and will start on every subsequent system startup as well.
On execution, the malware will make a copy of itself in the Window folders with the name %windir%\system32\ as CbEvtSvc.exe. The malware will then attempt to connect to a remote server and send information about the infected system. If this connection to the remote server is established, the malware may also be instructed to download and execute additional malware onto the infected system.
The spam e-mails contain a link or links; in this case, the links are "Usher re-hires mother as manager" and "FULL STORY". When the user clicks these links, a prompt will appear requesting the user to download and execute a file named adobe_flash.exe, which is purported to be necessary to read the full story. The downloadable file is in fact malware. Once the file is downloaded and installed, it then starts as a service and will start on every subsequent system startup as well.
On execution, the malware will make a copy of itself in the Window folders with the name %windir%\system32\ as CbEvtSvc.exe. The malware will then attempt to connect to a remote server and send information about the infected system. If this connection to the remote server is established, the malware may also be instructed to download and execute additional malware onto the infected system.