Worm.Win32.Dorkbot_0a7363c1dd

Dynamic Analysis

Payload

Behaviour	Description
WormAutorun	A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Worm's file once a user opens a drive's folder in Windows Explorer.
IRCBot	A bot can communicate with command and control servers via IRC channel.
MSNWorm	A worm can spread its copies through the MSN Messanger.
DNSBlocker	A program can block designated DNS servers for making it difficult for users to locate specific domains or web sites on the Internet.
UDPFlooder	This program can make a UDP flood. A UDP flood attack is a denial-of-service attack using the User Datagram Protocol (UDP). It can be initiated by sending a large number of UDP packets to random ports on a remote host.
SYNFlooder	This program can make a SYN flood. It is a form of denial-of-service attack in which an attacker sends a succession of SYN requests to a target's system in an attempt to consume enough server resources to make the system unresponsive to legitimate traffic.
Trojan-Proxy	This program can launch a proxy server (SOCKS4) on a designated TCP port.
USBInfector	A program can register a device notification with the help of RegisterDeviceNotification. So it is notified when a USB device is plugged and then the worm copies itself to the USB device plugged into the affected computer.

Process activity

The Worm creates the following process(es):

%original file name%.exe:256
%original file name%.exe:1500

The Worm injects its code into the following process(es):

mspaint.exe:1536
mscorsvw.exe:172

Mutexes

The following mutexes were created/opened:No objects were found.

File activity

The process mspaint.exe:1536 makes changes in the file system.

The Worm creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
%Documents and Settings%\%current user%\Application Data\Microsoft\Pukmkb.exe (15116 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\4PMNAL2B\desktop.ini (67 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\U327UNSX\desktop.ini (67 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\058JSPW5\desktop.ini (67 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\YVQTGDKH\desktop.ini (67 bytes)

The Worm deletes the following file(s):

C:\%original file name%.exe (0 bytes)

The process %original file name%.exe:256 makes changes in the file system.

The Worm creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Application Data\temp.bin (15116 bytes)

Registry activity

The process mspaint.exe:1536 makes changes in the system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Directory" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4]
"CacheLimit" = "65452"
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache4"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

"Cookies" = "%Documents and Settings%\%current user%\Cookies"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache2"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common AppData" = "%Documents and Settings%\All Users\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

[HKLM\System\CurrentControlSet\Hardware Profiles\0001\Software\Microsoft\windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"SavedLegacySettings" = "3C 00 00 00 13 00 00 00 01 00 00 00 00 00 00 00"

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "28 D2 B2 DA 6B 27 74 AF E4 CE 4B 69 39 3A 67 78"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache1"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"MigrateProxy" = "1"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"History" = "%Documents and Settings%\%current user%\Local Settings\History"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache3"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Paths" = "4"

The Worm modifies IE settings for security zones to map all local web-nodes with no dots which do not refer to any zone to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"UNCAsIntranet" = "1"

The Worm modifies IE settings for security zones to map all web-nodes that bypassing the proxy to the Intranet Zone:

"ProxyBypass" = "1"

Proxy settings are disabled:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

The Worm modifies IE settings for security zones to map all urls to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName" = "1"

To automatically run itself each time Windows is booted, the Worm adds the following link to its file to the system registry autorun key:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Pukmkb" = "%Documents and Settings%\%current user%\Application Data\Microsoft\Pukmkb.exe"

The Worm deletes the following value(s) in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"AutoConfigURL"
"ProxyServer"
"ProxyOverride"

The process %original file name%.exe:256 makes changes in the system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "1B F1 FD 6C A3 B0 C3 5B 78 E8 12 B8 85 51 22 CD"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

The process %original file name%.exe:1500 makes changes in the system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "B2 0B 9B D6 00 57 36 92 5A B8 F0 91 4B F2 6F 25"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

The process mscorsvw.exe:172 makes changes in the system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\.NETFramework\v2.0.50727\NGenService\State]
"AccumulatedWaitIdleTime" = "1260000"

Dropped PE files

There are no dropped PE files.

HOSTS file anomalies

No changes have been detected.

Rootkit activity

The Worm installs the following user-mode hooks in WININET.dll:

HttpSendRequestW
InternetWriteFile
HttpSendRequestA

The Worm installs the following user-mode hooks in DNSAPI.dll:

DnsQuery_A
DnsQuery_W

The Worm installs the following user-mode hooks in WS2_32.dll:

send
GetAddrInfoW

The Worm installs the following user-mode hooks in kernel32.dll:

MoveFileA
CopyFileW
CopyFileA
MoveFileW
CreateFileW
CreateFileA

The Worm installs the following user-mode hooks in ntdll.dll:

LdrLoadDll
NtResumeThread
NtQueryDirectoryFile
NtEnumerateValueKey

Propagation

A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Worm's file once a user opens a drive's folder in Windows Explorer.A program can register a device notification with the help of RegisterDeviceNotification. So it is notified when a USB device is plugged and then the worm copies itself to the USB device plugged into the affected computer.A worm can spread its copies through the MSN Messanger.

Removals

Remove it with Ad-Aware

1. Click (here) to download and install Ad-Aware Free Antivirus.
2. Update the definition files.
3. Run a full scan of your computer.

Manual removal*

1. Scan a system with an anti-rootkit tool.
   
2. Terminate malicious process(es) (How to End a Process With the Task Manager):

   %original file name%.exe:256
   %original file name%.exe:1500
   

3. Delete the original Worm file.
   
4. Delete or disinfect the following files created/modified by the Worm:

   %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
   %Documents and Settings%\%current user%\Application Data\Microsoft\Pukmkb.exe (15116 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\4PMNAL2B\desktop.ini (67 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\U327UNSX\desktop.ini (67 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\058JSPW5\desktop.ini (67 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\YVQTGDKH\desktop.ini (67 bytes)
   %Documents and Settings%\%current user%\Application Data\temp.bin (15116 bytes)

5. Delete the following value(s) in the autorun key (How to Work with System Registry):

   [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
   "Pukmkb" = "%Documents and Settings%\%current user%\Application Data\Microsoft\Pukmkb.exe"

6. Find and delete all copies of the worm's file together with "autorun.inf" scripts on removable drives.
   
7. Reboot the computer.
   

*Manual removal may cause unexpected system behaviour and should be performed at your own risk.

Static Analysis

VersionInfo

No information is available.

No information is available.

PE Sections

Name	Virtual Address	Virtual Size	Raw Size	Entropy	Section MD5
.code	4096	8049	8192	3.75713	5c3213257b257ec893473ca1dd2b9441
.text	12288	44359	44544	4.54102	9051650a121d69df95c25bf17a4b39ed
.rdata	57344	5672	6144	4.1962	f67d5cc0a228489854a5ed26fb7e67ae
.data	65536	4508	3584	3.49429	e5db1f4eb7d8caf3b226e27005c3ed65

Dropped from:

Downloaded by:

Similar by SSDeep:

Similar by Lavasoft Polymorphic Checker:

Total found: 47
35b316ae034d17b5363f48c7440ff3d4
3bd9b8103e4f603be74a66971c34b2de
7838d0a9c6cf6b096b44dc92e87adbbc
87511b74422726c9f4b416beb33b0be3
d3cf8cd8e185540c65e72aa44344c467
d07d999b6acaf79b27105dd44c5c5349
40f176b8d474932edeeb24e89878618a
2b49e00cd013915d2b729fe8abbc3edf
deb353e6a612ae5f24e060d81e5bd5d1
a77dc634d5b5972b6ab7f4912587e431
a6bec6d77556b161c0c87ef5e6cc4a7b
7c33afbe3152450c4bb53afabd9bc2ef
542caa4bff5ac02fe64700dd360491c5
489dc902a409efa84f0dbe0c406bfb9c
481ac48761d88eaf9319e7854b7a43d9
305e1dc21fe5a93c9824e00276f339b9
1b2096367c364ed02384b2fea40212d9
1423892baaebead1167395e972bdb9d1
1325ec0853ef568bd9c5eee5b91faab5
d7ba1f65283e4ed54284d32127b300f8
cd3f65f3316106ea67f2fbe5b41e1100
8f90b465169b06382716c56a109e09ae
682600e6ec3a0db5d280909adf44a7bb
4e9a94206aeedf81df0167e0f7c87980
0cd5e7f9d7ae8ad7a5acf40096a88ec2

Network Activity

URLs

IDS verdicts (Suricata alerts: Emerging Threats ET ruleset)

Traffic

Map

The Worm connects to the servers at the folowing location(s):

Strings from Dumps