Increase in European “Options” HTTP Scans from Linux Systems

Over the weekend, we saw a large increase in HoneyPoint captures of HTTP fingerprinting scans using the “Options *” technique. Even more interesting was that nearly all of these scans originated in Europe. The scans were all originated from Linux boxes and simple port probes show all of the boxes to be running OpenSSH 4.3 (some with p2). Other ports show no consistency on the originating systems.

Clearly, it could be a coincidence, but for multiple hosts to show only that correlating port, it could also be a specific exploit for OpenSSH 2.4. Additional research shows a few known issues with this version of OpenSSH. Perhaps a new bot-net is being launched by leveraging this vulnerability?

We are deploying additional SSH HoneyPoints to try and capture more data about possible exploitation of systems meeting these implementations.

Editor’s Note: The current version is OpenSSH 4.7/4.7p1 – so if you are using older versions (including 4.2/4.3) you should upgrade as soon as possible to the current revision.

Post revised to update for identified existing OpenSSH issues.