Monthly Archives: July 2017

Reyptson Ransomware

Lawrence Abrams for Bleeping Computer: Reyptson Ransomware Spams Your Friends by Stealing Thunderbird Contacts. He says:

‘…unfortunately there is no way to decrypt this ransomware currently for free. We have, though, setup a dedicated Reyptson Support & Help Topic for those who wish to discuss it or ask questions.’

Announcement by EMSIsoft’s @PolarToffee.

Notes from @malwrhunterteam

David Harley

Technology versus phone scammers

Not directly concerned with tech support scams, which have tended to be my main scam focus on this site, but David Bisson put up a very useful post – Google and Apple should do more to fight phone scammers, says researcher: Cooperation with government is key, but it’s only part of the solution… – expanding on a slightly naive article by David Glance for The Conversation – Phone scams cost billions. Why isn’t technology being used to stop them?.

David Bisson points out that:

At the end of the day, caller ID spoofing makes it next to impossible to consistently block phone scammers. As a result, users should focus on strengthening their mobile device security by exercising caution around text messages and phone calls delivered from unknown numbers. They should never click on links embedded in text messages sent from suspicious numbers. Also, they could always let an unknown phone call go to voice mail and use that subsequent record to evaluate the number’s legitimacy.

With reference to one of the scam types referenced there, I wrote about the ‘Can you hear me?’ scam, if that’s what it really is, for ESET: Scam calls: can you hear me, mother?

David Harley

AV-Test Report: malware/threat statistics

AV-Test offers an interesting aggregation of 2016/2017 malware statistics in its Security Report here. Its observations on ransomware may be of particular interest to readers of this blog (how are you both?) The reports points out that:

There is no indication based on proliferation statistics that 2016 was also the “year of ransomware“. Comprising not even 1% of the overall share of malware for Windows, the blackmail Trojans appear to be more of a marginal phenomenon.

But as John Leyden remarks for The Register:

The mode of action and damage created by file-encrypting trojans makes them a much greater threat than implied by a consideration of the numbers…

Looking at the growth in malware for specific platforms, AV-Test notes a decrease in numbers for malware attacking Windows users. (Security vendors needn’t worry: there’s still plenty to go round…)

On the other hand, the report says of macOS malware that ‘With an increase rate of over 370% compared to the previous year, it is no exaggeration to speak of explosive growth.’ Of Android, it says that ‘the number of new threats … has doubled compared to the previous year.’

Of course, there’s much more in this 24-page report. To give you some idea of what, here’s the ToC:

  • The AV-TEST Security Report 2
  • WINDOWS Security Status 5
  • macOS Security Status 10
  • ANDROID Security Status 13
  • INTERNET THREATS Security Status 16
  • IoT Security Status 19
  • Test Statistics 22

David Harley

Windows 10 Controlled folder access

Microsoft describes the new Windows 10 feature ‘Controlled folder access in Windows Defender Antivirus’ in the article Announcing Windows 10 Insider Preview Build 16232 for PC + Build 15228 for Mobile. The article specifically mentions ransomware as one of the threats against which it is likely to be effective.

The article states that ‘Controlled folder access monitors the changes that apps make to files in certain protected folders. If an app attempts to make a change to these files, and the app is blacklisted by the feature, you’ll get a notification about the attempt. You can complement the protected folders with additional locations, and add the apps that you want to allow access to those folders.’

It’s not clear what criteria are used to blacklist an application: as I read it, it may simply use Windows Defender’s scanning engine to determine the status of an app. I guess I’ll wait for more information before deciding how much additional protection this really provides.

Zeljka Zorz comments for Help Net Security :

Whether this security feature will be enough to stop ransomware remains to be seen, especially if ransomware can get a whitelisted application to bypass the protection and offer a way in.

I wasn’t really thinking of this in terms of whitelisting until I read that, but the feature does, in fact, allow the user to add protected locations apart from the default folders, and also to ‘ Allow an app through Controlled folder access’.  Which opens the door to social engineering as well as subversion of apps, but then that’s a persistent issue with whitelisting applications.

David Harley