Corporate cyber-attacks mostly happen on Friday

Cyren has today reported that criminals intensify their malware attacks on Fridays in order to take advantage of employees who are less protected over the weekend.

Monday was found to be one of the most common times for threats and breaches to appear on corporate networks due to employees downloading unsafe content on Saturdays and Sundays when using unsecured networks.

When employees take their devices home over the weekend, they often connect to the Internet through public or personal unsecured Wi-Fi networks, and proceed to surf the web, download content, and click on links delivered through email.

Examining daily malware distribution trends during Q3 2015, Cyren detected an average of 2.25 billion malware attachments on Fridays – that's more than triple the number seen on Mondays during the same quarter.

Cyren analysts believe this may be part of a long-term process in which criminals are trying to amass corporate login data to be sold and/or used in corporate breaches. The attacks may also be intended to target well-known webmail services that can be used to access corporate data.

"These malware and phishing findings come on the heels of Cyber Security Awareness Month as well as a fresh Cyren survey that underscores just how difficult it is for the average user to identify a threat," said Lior Kohavi, CTO at Cyren.

"Now, more than ever before, both individuals and enterprises should embrace cyber security awareness. Organisations must arm employees with knowledge of the vast, ever-changing tricks used by criminals."

Other report highlights include:

6.25 percent of installed Android apps are malicious
Spam hit a six-year low in September with an average of 47.4 billion daily spam emails sent that month
The average number of daily spam emails detected by Cyren decreased to 52 billion in Q3 from 55 billion in Q2
Phishing URLs tracked by Cyren are down 19 percent from Q2 to Q3 – likely a normalising trend from the significant jump seen in Q2.