It’s not a virus

(If you don’t read that title in your head the same way Arnold Schwarzenegger said “it’s not a tumor” in Kindergarten Cop, I’d argue you need to rethink your life choices. 😉)

I have a non-functional hot tub that needs repair, which is a problem as my wife and I are preparing to sell our house. (Bear with me for a minute, I’m going somewhere with this.)

When is a hot tub not a hot tub?

On Monday, I called a place that services and repairs hot tubs. I started to explain the issue and what we needed, but as soon as I said the words “hot tub,” the guy I was talking to interrupted. “You don’t have a hot tub,” he told me, “there’s no such thing. You have a spa.” I kid you not.

I’m sure you can imagine my reaction. I paused, trying to process what had just happened, and uttered a short “what the hell is going on here” laugh. In all honesty, there was a part of my brain that wanted to just hang up the phone right then and there.

Unfortunately, we really need the darn thing repaired, and I’d promised my wife I’d get it done, so I soldiered on, calling it a “spa.” Yet that word felt alien in my mouth, like I was talking about a place where someone might put hot rocks on me or dunk me into a tub full of mud – both exactly as appealing to me as I make them sound. Everyone I’ve ever encountered calls this thing a “hot tub.” Books, TV shows, movies, etc. It’s “Hot Tub Time Machine,” not “Spa Time Machine.”

The “hot tub” of the security world

After this encounter, it got me thinking. There’s a huge parallel between this conversation and conversations I’ve seen on security topics. I’ve seen – and, I imagine, have probably said – nearly the same pedantic phrase in another form. “You don’t have a virus, those are rare today. You have malware.”

In the security community, education of the user is of great importance. Thus, we often think that we need to correct terminology like this, to ensure the user understands. Malware is the more “correct” term these days, as the term “virus,” from a technical perspective, implies particular behaviors that most malware no longer exhibits.

However, think about my reaction when someone interrupted me to tell me I don’t have a hot tub. I felt disrespected, talked down to. If I’d been female, I’d have been justified in accusing him of mansplaining hot tubs – sorry, “spas!” – to me. (If a man mansplains to another man, is it still mansplaining?)

Now think about the results. I stuck with the conversation, but I really didn’t want to. That single comment very nearly caused that company to lose my business. The negative feelings could still affect the business relationship, if future interactions are even slightly off. I’m primed to dislike this guy, and the company he represents, if anything doesn’t go exactly right.

The same is likely to be true if you correct someone who tells you they have a “virus.” It may not be entirely logical, but human interactions seldom are.

Don’t be pedantic

The vocabulary used by security or IT professionals is very different from the vocabulary of non-technical people. To the layperson, “virus” is the term used by books, TV shows, and movies to refer to malware. This is the lens through which they see the concept.

No matter what role you have in security, it’s critical that you understand and accept this perspective. Sure, you may not like it, but that’s the way it is. If you are having a discussion with someone who thinks they’re infected with “a virus,” you’ve lost them immediately if you argue about their chosen terminology. You’ve suddenly become an adversary, rather than an ally. You may be able to come back from it, but it’ll take a lot more work.

Instead, focus on the user’s problem. Non-technical people these days are primed to call anything and everything that happens to their computer a “virus.” Help them discover the cause and fix it, regardless of what it is. Chances are, it’s not even malware at all.

Once you’ve fixed the problem, that’s your opportunity to explain the nuances to the user. At that point, they’ll be far more likely to be interested in hearing that the “virus” was actually an adware trojan, how it infected them in the first place, what threat it posed, and how to prevent it in the future.


Long story short, when you – as a technical person – have the task of assisting a non-technical person with a technical issue, it’s your job to adapt to the language that person understands, not vice versa. Failure to do that will lead to… well, failure.

How I became a Mac security researcher

Over the years, I’ve been attacked and criticized many times over my views on security. At times, it’s been completely justified, while other times, it stems from not knowing the things that I know.

Thus, spurred on by events that are ultimately unimportant, for the first time publicly, I’ve decided to tell the entire story of how I got into security, how I ended up at an antivirus company, and how and why my views have changed. This is the story of someone who went from a rabid “Macs don’t get viruses” fanboy to a professional malware researcher, and why exactly such a strange turn of events occurred. With a smattering of stories about the history of Mac malware thrown in. 🙂

“Macs don’t get viruses”

In January of 2006, I joined Apple’s discussion forums, termed “Apple Support Communities,” or ASC for short. Around this same time, I was attempting a poorly-thought-out transition to teaching high school science, which I would soon learn I was not cut out for. A few years later, I failed at it and quit before I could finish paying off the debt from getting my Master’s degree. My self-esteem was at an all-time low, and I vented steam at people on the forums. It was not a time I’m particularly proud of.

At that time, I firmly believed that the Mac’s malware problems from the early days were a thing of the past. Before OS X, Apple’s “Classic” system (as we call it now) had all manner of malware. In fact, the first widespread computer virus – the Elk Cloner virus, which appeared in 1982 – actually affected the Apple II computer, a precursor of the Macintosh, and not a PC running DOS or Windows.

Disinfectant logo

The early Macintosh was no stranger to threats, and antivirus software was soon to be considered important. John Norstad’s Disinfectant, introduced in 1989, was considered by many to be the best, though other early pioneers in the antivirus industry were also offering some of the first antivirus software on the Mac, such as McAfee’s VirusScan.

Working in the campus computer lab as a college student, I encountered my first piece of malware, a virus known as WDEF, which spread from disk to disk automatically, infecting any floppies inserted and spreading to the next Mac that used it. (The virus infected the “desktop file” present on every disk on the Classic Mac system.) Despite this, my interest in malware would not truly start until nearly two decades later.

Once Apple transitioned to the Unix-based OS X, all the old malware was suddenly obsolete. OS X was a drastically different system, viruses written for Classic systems no longer worked. On ASC, I routinely told people that Macs didn’t get viruses, thanks to my preconceived notions and lack of knowledge to the contrary, and, frankly, acted like a bit of a jackass.

Information tips the balance

At some point, someone – and I couldn’t tell you for the life of me who it was, or precisely when this happened, at this point – challenged me with some concrete information. I set out on a frenzy of research to refute his (her?) arguments. But my determination to prove that I was correct took a turn that would change my life: I learned that I was actually wrong!

Needless to say, this was a humbling experience. More importantly, though, I felt like I was glimpsing the periphery of a hidden world. I decided I wanted to know more.

Over the next few years, I believe that I dug up information on every piece of OS X malware that ever became publicly known. I knew the symptoms, the dangers, and how to remove every obscure piece of malware that nobody ever saw anymore. I started monitoring for and documenting the emergence of every new piece of malware. In 2011, I created The Safe Mac to serve as a repository for this knowledge and a way of educating people about the potential dangers.

The Safe Mac logo

I was still, at that time, a bit negative on the benefits of antivirus software. I was not nearly as rabid about it as I once was, of course, as I realized that it could provide a valuable service to some people, though I felt I personally did not need it, and that others who shared a similarly technical mindset didn’t need it either.

Adware Removal Guide

I started noticing an increase in a particular kind of malware that become known as adware, because its goal was to steal from advertisers, search engines, and other affiliate programs in general. In 2013, I knew I was onto something big when an adware company I had blogged about threatened to sue me if I didn’t remove all content about them from my website.

Genieo legal threat
Threat posted publicly in the comments on The Safe Mac

This was a particularly scary event, as this legal threat could jeopardize my family’s financial future. I ended up refusing their demands. They backed down, I breathed a sigh of relief, and I continued with my (unpaid) work.

In hindsight, this outcome probably could have been predicted due to the fact that Genieo rather amateurishly posted the threat publicly, for anyone to read. Still, this was an eye-opening event that underscored to me the idea that “adware is malware with a legal team.”

Since the adware problem had been on the rise, I was answering large numbers of questions on ASC about adware removal. In late 2013, I decided to create a set of pages on The Safe Mac that I called the Adware Removal Guide. These pages provided information to help the user figure out what adware they were infected with, and how to remove those infections.

Heading into 2014, I had learned that people had great difficulty following manual removal instructions. I do not mean to imply that they were stupid, as some would uncharitably say; they were simply unsure of themselves, or over-sure of themselves, or perhaps just not particularly careful readers. Whatever the case, I went through many iterations of my instructions, and through trial-and-error learned a lot about how to write those instructions clearly.

Creation of TSMART


In an ironic twist, it was the actions of that same adware company I had butted heads with that spurred me to try something different. Genieo’s adware was installing files in such a way as to render the system incapable of starting up if one file were removed without removing another. Countless people ran afoul of this issue after failing to follow my removal instructions to the letter, and some of them became very irate with me over the issue, as if it were my fault.

This, coupled with a timely suggestion from someone (who, I can no longer recall) that a shell script might be handy to automate removal, sparked an idea. Soon, the abysmally named TSM Adware Removal Tool (abbreviated TSMART) was born. This tool was written in AppleScript, compiled into an application to make it easy to run, and it automated removal of everything described in my removal instructions.

It wasn’t long before the adware makers escalated with techniques like randomizing file names, making my script more difficult to maintain. Every change required a complete update of the script, and although I built functionality to alert the user when an update was available, it just became too cumbersome.

I did a thing…

AdwareMedic logo

Thus was born the idea for AdwareMedic: an application that supported flexible identification logic coded into rules, which could be updated independently of the application itself. It certainly wasn’t my intention to build an antivirus program – indeed, AdwareMedic was specifically meant to target adware, not malware – but evolution sometimes results in two different paths to the same end.

The first version of AdwareMedic was written in a very short time – a weekend for the first prototype, and about a month for something that could be released, if memory serves. It was done as a fun project that could help some people. Next thing I knew, it had become a huge success. I didn’t have a formal way to track its usage, but I firmly believe that by early 2015 there were hundreds of thousands, maybe even millions, of Macs running AdwareMedic. I began to hear that Apple Geniuses were recommending it to people!

AdwareMedic became, I believe, the first real challenge to adware companies on the Mac platform. So much so that I saw adware responding and changing behaviors based on AdwareMedic detections. At one point, one piece of adware, called VSearch (also known as Pirrit), began fighting back by modifying the content of the AdwareMedic website when viewed from an infected machine… in the initial stages, by redirecting the Download button to the MacKeeper website.

I fought back, of course, with scripts designed to detect those modifications and show the user information about how to combat the issue. The VSearch folks escalated each time, eventually going so far as to block access to the AdwareMedic site by replacing the site’s content in the infected browser with a fake “server not found” page.

This behavior directly resulted in Apple adding rules for VSearch to the XProtect antimalware feature in macOS.

rule VSearchA 
         description = "OSX.VSearch.A" 
         Macho and
         filesize <= 2000000 and
         ( hash.sha1 ( 0 , filesize ) =="6c6acb179b232c0f1a6bb27699809320cc2c1529" or
         hash.sha1 ( 0 , filesize ) =="cebb19fee8fd72c0975ea9a19feea3b5ce555f94" or
         hash.sha1 ( 0 , filesize ) =="1503f1d7d275e976cd94cfd72929e0409e0cf76a" or
         hash.sha1 ( 0 , filesize ) =="c50adfa949a70b33d77050d7f0e2f86bccbc25cf" or
         hash.sha1 ( 0 , filesize ) =="40346b3946d7824d38f5ba71181f5c06805200af" ) 

Do you have time for a quick chat?

Next thing I knew, I got an e-mail from Malwarebytes CEO Marcin Kleczynski. I didn’t know much about them, but what I read was intriguing, and Marcin was very straightforward.

When I flew out to California for a meeting, I learned that Malwarebytes started out in an almost identical fashion. Marcin started out on forums, after having infected the family computer. He built up a foundation of knowledge, with the help of some friends made on forums, and built a product. In a million years, I couldn’t have imagined a better fit.

Once I was on board at Malwarebytes, a whole world of possibilities opened up. With AdwareMedic, I had never dared to remove certain things. My experience with Genieo made me gunshy. I simply couldn’t afford to risk a lawsuit, and yet adding and later walking back a detection would be nearly as bad, as it would show that I could be bullied into submission.

Malwarebytes does not tolerate PUPs (potentially unwanted programs), and isn’t afraid to go to court when threatened by PUP vendors. With Malwarebytes at my back, I was finally able to start doing things that AdwareMedic users had been requesting for a long time – like removal of MacKeeper!

The end…?

Thus ends the story of how I went from rabid Mac malware denier to a creator and proponent of security software. If you were to ask me to sum up with one single thing that pulled me in this direction, that thing would be knowledge. It’s easy to have strong opinions in a position of ignorance. It’s also easy to keep those opinions if you never challenge your own preconceptions. But it’s very hard to maintain an opinion in the face of contrary information, and you’ll never discover that information if you don’t seek it out.

Of course, this is only the end of the story of how I got here. I’ll have more stories to tell from the trenches in the future, as I fully intend to keep fighting the scumbags that are intent on turning my favorite platform into a cesspool of malware and crapware.

My years of research and experience in the trenches taught me an important lesson: people need help. It’s not their fault that they’re getting infected. The creators of malware, adware, and other unwanted programs are extremely good at tricking people, and they’re not going to stop. We’re slowly heading towards a world where Mac malware becomes as sophisticated as what’s seen on Windows.

Even now, not all threats involve tricking the user… sometimes, malware spreads through stealthy techniques that infect even the most savvy among the tech community. As an example, read the story of how Panic, Inc got hacked.

My request to you, dear reader, is this: spread the word. Mac malware does exist. Mac adware is just a millimeter shy of malware, and you don’t want that infection any more than you want malware. In fact, I’d willingly infect myself with certain pieces of malware before I would do the same with most of the adware out there!

Am I saying you have to force your friends and family install antivirus software? No. I believe it is a useful tool for many people, but I also admit it’s not a silver bullet. I make antivirus software, and I’m telling you my software is not, and never will be, perfect! Anyone telling you differently about their own software is lying to you.

Whatever you do, if you are able, help those you know to stay safe online, in whatever way suits them best. Just keep in mind that what suits someone best is not always what suits you best… that’s a lesson I’ve learned the hard way, repeatedly.