Repairmen suspected of installing ransomware on customers’ PCs. Arrests in South Korea

According to a report by Catalin Cimpanu at The Record, authorities in South Korea have filed charges against employees at a computer repair store.

What are the nine charged employees of the unnamed company based in Seoul alleged to have done? Created and installed ransomware onto the computers of their customers, netting more than 360 million won (approximately US $320,000.)

The report says that South Korean police claim the extortion scam began last year, after companies contacted the repair firm hoping to receive assistance in dealing with ransomware infections that had encrypted their systems.

The repair firm reportedly initially assisted victims, helping them negotiate and pay ransoms to retrieve data garbled by the attacks. However, according to The Record, “in at least 17 incidents, the employees modified ransom notes to inflate the original ransom demands in order to obtain larger funds from the victimized companies.”

In some cases the ransoms are said to have been increased ten-fold, allowing corrupt technicians to make large profits when victims agreed that a ransom demand should be paid.

That would be bad enough, but it is further claimed that technicians at the repair store installed a remote access backdoor on customers’ computers they helped recover from attacks, and would use it to launch their own ransomware attacks.

Ultimately, according to reports, the rogue staff would plant ransomware onto the computers of any customers – even those who didn’t bring their computers in due to a ransomware problem.

If there’s one thing that I thought ransomware gangs had learnt in recent years it was not to target organisations on your doorstep.

Just look at the amount of ransomware believed to originate from certain parts of Eastern Europe, but which notably goes out of its way to avoid infecting computers if it detects a Cyrillic keyboard is being used.

The theory goes that law enforcement agencies in Russia might be turning a blind eye to ransomware gangs based in the country, just so long as they don’t cause problems for companies close to home.

For instance, according to an analyis by security experts at Cybereason, the DarkSide ransomware deliberately strives to avoid infecting computers it identifies as being based in the following countries:

• Armenia
• Azerbaijan
• Belarus
• Georgia
• Kazakhstan
• Kyrgyzstan
• Moldova
• Romania
• Russia
• Syria
• Tajikstan
• Tatarstan
• Turkmenistan
• Ukraine
• Uzbekistan

If South Korean police really have successfully identified members of an active ransomware gang, it sounds like the suspects may have made the elementary mistake of targeting companies far too close to home.

In the past we’ve described how stores offering repair services have tricked customers into believing their PCs are infected with malware. It’s something else to take a PC to a repair shop for fixing, only to find that you’re dealing with a potentially bigger criminal than the ones who have caused your computer to seize up in the first place.