In the late 1980s, Buchwald was a social engineer, with the ability to manipulate phone system employees anywhere in the United States. In addition, he had a hacking skill with regard to Bell and AT&T systems (specifically COSMOS, SCCS, and LMOS), which allowed him virtually unrestricted access to phone lines, including the ability to monitor conversations, throughout the country. He was the lead author of the PENIX suite of hacking tools. Some of his original ideas are still in use by social engineers and security professionals today.
In 1995, Dave served as a technical consultant to the movie Hackers, editing the screenplay and personally coaching many of the principal cast.
In 1997, Buchwald co-founded Crossbar Security with Mark Abene (a.k.a. Phiber Optik) and Andrew Brown. Crossbar provided information security services for a number of large corporations, but became a casualty of the dot-com bubble. Crossbar Security went defunct in 2001, largely due to cuts in corporate security spending and an increase in the cost of corporate computer security advertising.
Buchwald works as a film editor and freelance photographer in New York City. He has been regularly producing cover art for 2600 Magazine since 2000 using the pseudonym Dabu Ch'wald. In August 2006, he completed his first feature film, Urchin. He has recently produced and edited the independent film Love Simple and is in pre-production on the film Kuru, the second movie by the production company The Enemy. A short he edited entitled Floating Sunflowers won the Gold Remi award for Best Comedy Short at the 47th Worldfest-Houston International Film and Video Festival in April 2014.
- "Hackers". Archived from the original on 2008-06-12. Retrieved 2008-07-09.
- Guterman, Jimmy (1997-10-10). "Grow Up Kid". Forbes. Retrieved 2008-07-09.
- "Concerned Telecom and Network Security Specialists Respond to Claims of GSM Cellular Phone Cloning". GSM Security. 1998-04-13. Archived from the original on 2008-02-26. Retrieved 2008-07-09.
- Scheib, Ronnie (2009-08-26). "Love Simple review". Variety. Retrieved 2008-08-31.