The Social EngineeringIn the beginning scenes of the movie, we see Harry posing as a police officer (highly illegal I might add, but he's a criminal and doesn't care). He's trying to identify who is the adult of the house. Repeated attempts of "Are your parents home? Do they live here?" to the children scrambling about the massive home lead him to eventually talk to Peter (Kevin's father, played by John Heard) and, later, Kate (Kevin's mother, played by O'Hara). From a social engineering perspective, Harry is using a police officer pretext to canvas the neighborhood in order to pick targets to rob. From Dr. Cialdini's 6 Principles of Persuasion (2006), he is leveraging Authority, Commitment/Consistency, and to a degree (except to Kevin), Likeability. The canvasing is all done as part of Harry's ploy to have the families tell him what he wants to know so that he can expedite his burglaries. If Harry had wanted to implement the other 3 Principles, he could have offered a house key escrow service that all the successful families on Lincoln Blvd (the street where the McAllisters lived) were doing for Social Proof. Adding another family's last name as someone who had already opted in would have built even more rapport. He could have sold "Police Bonds" for additional sweeps of the street or house with only so many available for scarcity and reciprocity. Moving forward through the movie, we repeatedly see Kevin use audio from "Angels with Filthy Souls" to foil people at the door, namely Harry, Marv, and the pizza delivery guy from Little Nero's. (They deliver in 20 minutes, or it is free.) The move is used to create the illusion that someone else is in the house. I do similar things when vishing. I typically play office sounds or store/cash register sounds from YouTube loudly in the background to sound like I am in these locations. When Kevin is shopping and is asked where his parents are, he responds with the traditional, early 90s "Stranger Danger" answers. After Marv hears the audio from Angels with Filthy Souls and tells Harry, they decide to case out the house. When they come back after dark, Kevin has already engineered a way to make it look like a big party is going on using a toy train, lots of string/rope, and Buzz's Michael Jordan standup. Once the home invasions start, (Harry and Marv are maimed endlessly in things that outside of a movie would kill them.) Kevin shows ingenuity in devising his booby traps. Kevin cleverly attracts or tricks them into falling for more of his traps.
The OPSEC AnglesPer Peter, the McAllister family had door locks and light timers (That's as good as anyone can do) when they talked to "Officer Harry." Door locks, sure. Those are standard. The light timers are what gives the family away even if he didn't disclose it to Harry. While not particularly OSINT, Harry and Marv could've easily parked nearby for a week or so before the week that they planned to rob the houses and observed the times of lights coming on. If they were persistent, they could've started a couple of weeks earlier to see if any patterns changed closer to the holiday. Other patterns that Harry and Marv could have observed easily (and not only after sunset) are trash days and cars. A simple drive through a neighborhood before 8 am daily would have told would-be attackers what day the trash runs occurred. Closer to the holiday, they could have observed whose trash cans were not by the curb on Wednesday. People don't typically miss trash day. With regards to the cars, Harry and Marv could have observed whether they were moved in a few days, whether they're generally backed in or pulled in forward, and whether the garage doors had been opened. The McAllisters left their garage doors open the whole time they were gone, after all. I recognize that there are mitigations to prevent showing you're out of town on trash day or what-not, but I also want to educate readers about their trends and what people, criminals or not, can ascertain. Peter's message on the answering machine is what gave Kevin up. For the most part, that is not much of a problem today since people have moved to cell phones and email instead of answering machines. The 2019/2020 alternative that could have the same impact is an out-of-office response or irresponsible posting to social media without proper access controls or calling someone who is outside or in public when they have you on speakerphone. Regarding Harry and Marv, let's just say that Marv would not make a good OPSEC instructor. He is too loose and constantly spills the beans about what he and Harry are planning, especially given what he tells us in Home Alone 2 (which will be covered in a later article.) The fact that the phone number on their van is JK5-1350 translates to 555-1350 should set off alarms for anyone outside Hollywood. To fit in better, Harry and Marv could have abandoned the van and walked a dog around the neighborhood. Given the perceived affluence of the community, they would have likely needed a purebred dog (This was before people were conscientious about mixed breeds and pound puppies) and altered their appearance to fit in. The van itself could've been used to their advantage after Marv started flooding houses to become the Wet Bandits.
Final ThoughtsIn conclusion, criminals are not always smart, cunning, OSINT, aware of social engineering or OPSEC savvy, but neither are consumers and victims. Sometimes one can do everything "right" and still fall victim. My parting message to you is to be wary of police officers going door to door (especially without a car) asking for information, alter your patterns frequently to make an un-pattern of sorts, and take your entire family with you. If you have to leave one behind, choose the one that is innovative with torturing intruders and leave them Micro Machines and breakable glass ornaments. If you have home IOT/automation devices, leverage them to the extent to which you're comfortable. I would be curious to see how the 1990 movie would translate into 2019 and 2020 with the new technologies and devices, including those we could use today for social engineering. Be safe.