Hiding the Referrer


When you investigate a malicious site opening or malicious file download, oftentimes you want to find out how your user got there. Checking the referrer information in proxy logs is one of the most trivial things to do if you want to identify the root cause, the initial site. Unfortunately, there are ways for an attacker to create a site that will alter or hide the referrer information. If the logs do not have the required referrer information and you are not aware that they can be hidden, you can incorrectly assume that there was no referrer at all.
Read more

DNS investigation on Windows

Recently, a friend of mine has asked for my help in an investigation. In his SIEM system, he saw that a machine generated some DNS sinkhole events, but he couldn’t find the originally requested DNS by the host. The events were generated because the machine tried to resolve a DNS hostname which was marked as malicious in the DNS Server. Unfortunately due to the huge amount of DNS requests in a network, this company did not store the DNS events in the SIEM.
Read more