Beste dames en heren,
Wij hebben al voor de zoveelste keer last van dat wij op de Blacklist komen van CBl en Spamhause.
Wij hebben al alles nagekeken en gescand.
We hebben alles opgeruimd of opnieuw geïnstalleerd.
Sinds gisteren staan wij er op en weet gewoon niet waar het vandaan kan komen uit ons bedrijfsnetwerk.
Kan iemand mij advies geven hoe ik het moet oplossen?
Zie hieronder het de melding die CBL geeft (ik heb ons IP uit voorzorg weggehaald.
IP Address 000.000.00.000 is listed in the CBL. It appears to be infected with a spam sending trojan or proxy.
It was last detected at 2011-12-20 08:00 GMT (+/- 30 minutes), approximately 1 days, 2 hours, 30 minutes ago.
It has been relisted following a previous removal at 2011-08-09 09:53 GMT (134 days, 3 minutes ago)
This IP is infected with, or is NATting for a machine infected with Torpig, also known by Symantec as Anserin.
This was detected by observing this IP attempting to make contact to a Torpig Command and Control server at 84.163.155.29, with contents unique to Torpig C&C command protocols.
Torpig is a banking trojan, specializing in stealing personal information (passwords, account information, etc) from interactions with banking sites.
Torpig is normally dropped by Mebroot. Mebroot is a Rootkit that installs itself into the MBR (Master Boot Record).
With Mebroot or any other rootkit that installs itself into the MBR, you will either have to use a "MBR cleaner" or reformat the drive completely - even if you manage to remove Torpig, the MBR infection will cause it to be reinfected again.
The best way to find the machine responsible is to look for connections to the Torpig C&C server. This detection was made through a connection to 84.163.155.29, but this changes periodically. To find these infections, we suggest you search for TCP/IP connections in the following ranges:
CIDR format Range format
91.19.0.0/16 91.19.0.0-91.19.255.255
91.20.0.0/16 91.20.0.0-91.20.255.255
84.163.0.0/16 84.163.0.0-84.163.255.255
usually destination port 80 or 443, but you should look for all ports. This detection corresponds to a connection at 2011-12-20 07:37:23 (GMT - this timestamp is believed accurate to within one second).
These infections are rated as a "severe threat" by Microsoft. It is a trojan downloader, and can download and execute ANY software on the infected computer.
You will need to find and eradicate the infection before delisting the IP address.
We strongly recommend that you DO NOT simply firewall off connections to the sinkhole IP addresses given above. Those IP addresses are of sinkholes operated by malware researchers. In other words, it's a "sensor" (only) run by "the good guys". The bot "thinks" its a command and control server run by the spambot operators but it isn't. It DOES NOT actually download anything, and is not a threat. If you firewall it, your IPs will remain infected, and they will still be able to download from real command & control servers run by the bot operators.
If you do choose to firewall these IPs, PLEASE instrument your firewall to tell you which internal machine is connecting to them so that you can identify the infected machine yourself and fix it.
We are enhancing the instructions on how to find these infections, and more information will be given here as it becomes available.
Virtually all detections made by the CBL are of infections that do NOT leave any "tracks" for you to find in your mail server logs. This is even more important for the viruses described here - these detections are made on network-level detections of malicious behaviour and may NOT involve malicious email being sent.
This means: if you have port 25 blocking enabled, do not take this as indication that your port 25 blocking isn't working.
The links above may help you find this infection. You can also consult Advanced Techniques for other options and alternatives. NOTE: the Advanced Techniques link focuses on finding port 25(SMTP) traffic. With "sinkhole malware" detections such as this listing, we aren't detecting port 25 traffic, we're detecting traffic on other ports. Therefore, when reading Advanced Techniques, you will need to consider all ports, not just SMTP.
Pay very close attention: Most of these trojans have extremely poor detection rates in current Anti-Virus software. For example, Ponmocup is only detected by 3 out of 49 AV tools queried at Virus Total.
Thus: having your anti-virus software doesn't find anything doesn't prove that you're not infected.
While we regret having to say this, downloaders will generally download many different malicious payloads. Even if an Anti-Virus product finds and removes the direct threat, they will not have detected or removed the other malicious payloads. For that reason, we recommend recloning the machine - meaning: reformatting the disks on the infected machine, and re-installing all software from known-good sources.
Wij hebben al voor de zoveelste keer last van dat wij op de Blacklist komen van CBl en Spamhause.
Wij hebben al alles nagekeken en gescand.
We hebben alles opgeruimd of opnieuw geïnstalleerd.
Sinds gisteren staan wij er op en weet gewoon niet waar het vandaan kan komen uit ons bedrijfsnetwerk.
Kan iemand mij advies geven hoe ik het moet oplossen?
Zie hieronder het de melding die CBL geeft (ik heb ons IP uit voorzorg weggehaald.
IP Address 000.000.00.000 is listed in the CBL. It appears to be infected with a spam sending trojan or proxy.
It was last detected at 2011-12-20 08:00 GMT (+/- 30 minutes), approximately 1 days, 2 hours, 30 minutes ago.
It has been relisted following a previous removal at 2011-08-09 09:53 GMT (134 days, 3 minutes ago)
This IP is infected with, or is NATting for a machine infected with Torpig, also known by Symantec as Anserin.
This was detected by observing this IP attempting to make contact to a Torpig Command and Control server at 84.163.155.29, with contents unique to Torpig C&C command protocols.
Torpig is a banking trojan, specializing in stealing personal information (passwords, account information, etc) from interactions with banking sites.
Torpig is normally dropped by Mebroot. Mebroot is a Rootkit that installs itself into the MBR (Master Boot Record).
With Mebroot or any other rootkit that installs itself into the MBR, you will either have to use a "MBR cleaner" or reformat the drive completely - even if you manage to remove Torpig, the MBR infection will cause it to be reinfected again.
The best way to find the machine responsible is to look for connections to the Torpig C&C server. This detection was made through a connection to 84.163.155.29, but this changes periodically. To find these infections, we suggest you search for TCP/IP connections in the following ranges:
CIDR format Range format
91.19.0.0/16 91.19.0.0-91.19.255.255
91.20.0.0/16 91.20.0.0-91.20.255.255
84.163.0.0/16 84.163.0.0-84.163.255.255
usually destination port 80 or 443, but you should look for all ports. This detection corresponds to a connection at 2011-12-20 07:37:23 (GMT - this timestamp is believed accurate to within one second).
These infections are rated as a "severe threat" by Microsoft. It is a trojan downloader, and can download and execute ANY software on the infected computer.
You will need to find and eradicate the infection before delisting the IP address.
We strongly recommend that you DO NOT simply firewall off connections to the sinkhole IP addresses given above. Those IP addresses are of sinkholes operated by malware researchers. In other words, it's a "sensor" (only) run by "the good guys". The bot "thinks" its a command and control server run by the spambot operators but it isn't. It DOES NOT actually download anything, and is not a threat. If you firewall it, your IPs will remain infected, and they will still be able to download from real command & control servers run by the bot operators.
If you do choose to firewall these IPs, PLEASE instrument your firewall to tell you which internal machine is connecting to them so that you can identify the infected machine yourself and fix it.
We are enhancing the instructions on how to find these infections, and more information will be given here as it becomes available.
Virtually all detections made by the CBL are of infections that do NOT leave any "tracks" for you to find in your mail server logs. This is even more important for the viruses described here - these detections are made on network-level detections of malicious behaviour and may NOT involve malicious email being sent.
This means: if you have port 25 blocking enabled, do not take this as indication that your port 25 blocking isn't working.
The links above may help you find this infection. You can also consult Advanced Techniques for other options and alternatives. NOTE: the Advanced Techniques link focuses on finding port 25(SMTP) traffic. With "sinkhole malware" detections such as this listing, we aren't detecting port 25 traffic, we're detecting traffic on other ports. Therefore, when reading Advanced Techniques, you will need to consider all ports, not just SMTP.
Pay very close attention: Most of these trojans have extremely poor detection rates in current Anti-Virus software. For example, Ponmocup is only detected by 3 out of 49 AV tools queried at Virus Total.
Thus: having your anti-virus software doesn't find anything doesn't prove that you're not infected.
While we regret having to say this, downloaders will generally download many different malicious payloads. Even if an Anti-Virus product finds and removes the direct threat, they will not have detected or removed the other malicious payloads. For that reason, we recommend recloning the machine - meaning: reformatting the disks on the infected machine, and re-installing all software from known-good sources.
