The week in security: Cybercrims hacking for gold in Rio; Caution on 100% ransomware blocking

As the Rio Olympics neared the opening ceremony, cybercriminals were also lacing up their running shoes with the establishment of many malicious domains and servers in Brazil. Real-world crime was also a risk, with warnings that stealing payment-card data is easy and an inexpensive bit of electronics able to hack hotel room locks and point-of-sale systems.

One mergers and acquisitions expert was warning that many companies discover, too late, that acquired companies have lingering security issues that present unacceptable risk for them. Many Australian businesses have deficient risk controls that may have implications on the insurance front, one legal expert warned, while experts were warning businesses not to take SentinelOne's $1m ransomware guarantee as an excuse not to adequately protect themselves.

Yet there were other claims about blocking ransomware, with researchers suggesting correct management of administrator rights can stop 100% of ransomware. Reports suggested almost half of US businesses had been hit by ransomware but only 3 percent paid up in the end.

Black Hat brought the usual assortment of frightening prognostications and how-tos, including guidance on developing malicious USB keys, a call for an upgrade to the 'cyber kill chain' concept, and a contemporaneous hacking challenge that set machine against machine in an exercise – won by a team from Pittsburgh, USA – that offered a glimpse into the automated future of cybersecurity.

Even as a researcher hid malware inside legitimate, digitally-signed files, Apple announced an invitation-only bug-bounty program, which is focused more on quality than quantity.

Meanwhile, government technologists at the Technology in Government conference in Canberra suggested open data was a key driver for open government and some researchers were suggesting that hackers are targeting opponents of China's claim in the South China Sea.

Iris scanning was becoming a reality in the smartphone arena, while a 'scareware' Trojan was said to have infected 2.8m Android devices and there were warnings that 200m Yahoo accounts may have been compromised. This led to calls for users to update passwords – and to update password managers like LastPass.

Google began rolling out HTTP Strict Transport Security to ensure that people use secure versions of Google's services. One Black Hat speaker was calling for a federal government agency focused on fixing the Internet's problems. And it's good that someone is improving cloud security, because a new study suggests Australian CISOs are still not aware of the actual status and security of cloud services within their organisations.

Microsoft has launched a service to evaluate the status and security of Office 365 implementations, while one organisation whose security status became very clear was Banner Health, a US hospital provider that wrote to 3.7m patients that it had been hacked and that their data may have been compromised. And a European Union lawmaker was concerned that Tinder is taking too much personal information.

Dropbox released new functionality to improve security and control over team-based collaboration. Some security specialists were highlighting the importance of metadata in delivering security analytics, while others were contemplating Hillary Clinton's pronouncement that she would push to stop terrorists using social media as extremist hunting grounds.

Even as some warned that drones could be used for industrial sabotage, the Russian security service said spies had planted malware on critical infrastructure, while Interpol arrested a Nigerian email scammer who had stolen more than $US60 million ($A80m) from victim businesses.