What is Server Message Block (SMB)and Why is it Important to Me as an Ethical Hacker?

The Server Message Block (SMB) protocol has been around a long, long time. And it has gone through updates over the years, mostly because lots of vulnerabilities have been exploited in this protocol.

History

In the 1980s the SMB protocol was initially developed by IBM for their PC LAN networking system. I remember the days of IBM PS/2 PCs (proprietary as heck), and token ring networking (yay MAUs!)

Back in those days, you had a computer running the Disk Operating System (DOS), and, while there were knock-offs, the two big players were IBM PC-DOS, and Microsoft’s MS-DOS. (Those of you who worked with DOS back in the day might also fondly remember a product called Dr DOS — or DR-DOS as well.) DOS consisted of a black screen with white lettering, and you could only run one application at a time.

Bill Gates’ company Microsoft had been hired by IBM to work on the DOS operating system. However, tensions arose due to IBM’s ongoing development work on a windowed OS called OS/2, and Microsoft’s own ventures into what would one day become Microsoft Windows. There was a splitting of the sheets, and Gates went his way and sold scads of copies of MS-DOS, while IBM, well, not so much.

You might be able to argue who had the better version of DOS, but you can’t argue who the clear winner was in the DOS wars. It was all about Microsoft at that point.

This is kind of a sad legacy of IBM’s. It seems as though every time they get something successful going in the PC market, they divest themselves of it. They had a good thing going with PS/2 computers until the whole “IBM clone” phenomenon hit consumers. Manufacturers started coming out with PCs that would run DOS, but getting other software to run could be problematic. Vendors began saying their software was “IBM PS/2 or IBM clone-compatible” and that was what got the ball rolling toward moving away from expensive PS/2 computers into less expensive clones. That didn’t mean that if you had a clone certain software products would run on it, but the clones took off nonetheless.

Moreover (and I’m editorializing a bit here), IBM also had a darn good product in their ThinkPad laptops and wound up…