Symantec, in its November 2011 Symantec Intelligence Report, says that the number of daily targeted attacks has increased four-fold compared to January this year. On average 94 targeted attacks were blocked each day during the month of November.
Further analysis reveals that in the US at least one attack is being blocked each day, and that one in 389 users may be the recipient of such an attack. In Japan, at least one attack is blocked nearly every nine days, and it may only be sent to one in 520 individuals.
The public sector has been identified as the most frequently targeted industry during 2011, with approximately 20.5 targeted attacks blocked each day. The chemical & pharmaceutical industry was second highest ranked, with 18.6 blocked each day. In this latter case, many of these attacks surfaced later in the year, broadly classified as the Nitro attacks. Similarly, this is also the case for the manufacturing sector, which was placed third most-targeted with approximately 13.6 attacks blocked each day.
Symantec cloud senior intelligence analyst Paul Wood said the aim of these targeted attacks is to establish persistent access to the targeted organisation’s network, in many cases with the aim of providing remote access to confidential data. "They have the potential to cause serious damage to an organization and in the long term represent a significant threat against the economic prosperity of many countries," Wood adds.
This month’s analysis indicates that large enterprises consisting of more than 2,500 employees received the greatest number of attacks, with 36.7 being blocked each day. By contrast, the small-to-medium sized business sector with less than 250 employees had 11.6 attacks blocked daily.
While targeted attacks are on the increase, the global spam rate has now reached its lowest level in three years. The effect of spam volumes three years ago was very dramatic and spam accounted for 68.0% of global emails. Recently the decline has been much slower, but spammers have also adapted to using more targeted approaches and exploiting social media as alternatives to email. Pharmaceutical spam is now at the lowest it has been since we started tracking it, accounting for 32.5 % of spam, compared with 64.2% at the end of 2010.
The global ratio of spam in email traffic in November fell by 3.7 percentage points since October to 70.5%, while the global phishing rate increased by 0.04 percentage points, taking the average to one in 302.0 emails (0.33%) that comprised some form of phishing attack.
The global ratio of email-borne viruses in email traffic was one in 255.8 emails (0.39 percent) in November, a decrease of 0.03 percentage points since October 2011. Further analysis also shows that 40.2 percent of email-borne malware contained links to malicious web sites, an increase of 20.1 percentage points since October 2011.
Web-based malware threats in November averaged 4,915 web sites each day harbouring malware and other potentially unwanted programmes including spyware and adware; an increase of 47.8% since October 2011.
The most frequently blocked malware for the last month was WS.Trojan.H.
