The common conception of cyber attacks are kind of like bad weather, ranging from irritating to catastrophic, but always unpredictable. Hackers are simply too sophisticated to draw any reliable judgments about, and we shouldn’t try.

As it turns out, some hackers are fairly predictable in their successful use of really dumb attacks. Here are the top five.

1.  Browser Locker
Browser locker, better known as the fake blue screen of death, spraying gibberish errors at the user and imploring them to call an Indian boiler room to be scammed at an average cost of $500. Some feature tweaks by the major browsers have pushed tech support scammers into more creative iterations, including registry hacks to replace the Windows shell itself with a locker. But the browser locker still exists in bulk and still draws victims.  Some lockers show some ingenuity, like manipulating the browser’s history function, but most are some variation of:

For x in range (a lot) {
  Alert(“You have a virus, please call Scam Number”)
}

2. DDOS Extortion
With DDoS bots for sale, sometimes on the clearnet, denial of service itself is not the most sophisticated of attacks. DDoS extortion is one notch lazier: an attacker will simply send an email to a corporate security staff threatening massive attacks if a bitcoin ransom isn’t paid immediately. Given that the ransom in question has tended to be relatively low, companies in industries requiring continuous uptime have sometimes shrugged their shoulders and paid. If this happens to you, talk to your service provider to work out mitigations. Don’t talk to the attacker.

3. SQL Injection
SQL Injection takes a modicum of technical skills to pull off, from finding the vulnerable site, to executing and safely exfiltrating dumped files or data. So why is this a dumb attack? Because it was first publically discussed in 1998. It was in the OWASP top 10 in 2007 and 2010. It was #1 on the OWASP top 10 in 2013. This is a known, predictable attack with extensive mitigations, so continuing to see it used so frequently is profoundly dumb.

4. Business Email Compromise
Sometimes, bosses are jerks. Sometimes when a boss is a jerk, their subordinates are too frightened to question an order from the boss, regardless of how out of character it might be. Attackers have weaponized this cliché of the business world by posing as the aforementioned jerk boss and demanding that large amounts of money be wired to overseas accounts as soon as possible. This scam, which is not much more complicated than shouting “Give me money!” is called Business Email Compromise and has cost US victims $960,708,616 since 2013.

5. Macro Malware
In the old days, MS Office had macros enabled by default. This made for a great malware delivery vector with malicious attachments that would run all sorts of arbitrary code when opened. Eventually, Microsoft had enough and switched Office macro support to off by default. Criminals have gotten around this restriction by simply asking the user to enable macros and thereby the malicious code. Here’s the technique cropping up in 2014 and here it is again last month.

In summary, a great many cyber threats are not sophisticated nation-state level, well thought out attacks. The bulk, in fact, tend to be the least effort required for success, which sometimes turns out to be not very much effort at all.