(NOTE: Sumo Logic was not and is not vulnerable to this attack, and all of our BASH binaries were patched on Wednesday night.)
Right now there is a massive land-grab going on, as dozens of criminal hacker groups (and others) are looking to exploit this widespread and serious vulnerability for profit. Patching this vulnerability while simultaneously sifting through massive volumes of data looking for signs of compromise is a daunting task for your security and operations teams. However, Sumo Logic’s patent pending LogReduce technology can make this task much easier, as we demonstrated this morning.
Way Big Data
While working with a customer to develop a query to show possible exploitation of Shellshock, we saw over 10,000 exploitation attempts in a fifteen minute window. It quickly became clear that a majority of the attempts were being made by their internal scanner. By employing LogReduce we were able to very quickly pick out the actual attack attempts from the data-stream, which allowed our customer to focus their resources on the boxes that had been attacked.
Fighting the Hydra
From a technical perspective, the Shellshock attack can be hidden in any HTTP header; we have seen it in the User-Agent, the Referrer, and as part of the GET request itself. Once invoked in this way, it can be used to do anything from sending a ping, to sending an email, to installing a trojan horse or opening a remote shell. All of which we have seen already today. And HTTP isn’t even the only vector, but rather just one of many which may be used, including DHCP.
So- Shellshock presents a highly flexible attack vector and can be employed in a number of ways to do a large variety of malicious things. It is is so flexible, there is no single way to search for it or alert on it that will be completely reliable. So there is no single silver bullet to slay this monster, however, LogReduce can quickly shine light on the situation and wither it down to a much less monstrous scale.
We are currently seeing many different varieties of scanning, both innocent and not-so-innocent; as well as a wide variety of malicious behavior, from directly installing trojan malware to opening remote shells for attackers. This vulnerability is actively being exploited in the wild this very second. The Sumo Logic LogReduce functionality can help you mitigate the threat immediately.