Malicious spam emails have seen a huge rise since the beginning of August, according to M86 Security.
The recent rise has seen levels "far exceed" anything the company has seen over the last two years, including prior to the takedown of the SpamIt operation last October, M86 said.
Last week 13% of the spam emails received by the M86 labs were considered malicious, which the company described as "unusual". On Monday of this week however that figure jumped to 24%. The majority of the malicious spam was being sent from the Cutwail botnet but Festi and Asprox were also contributing.
"In April this year, we reported on a spike in malicious spam. Yes, that was a significant increase but not as massive as we have observed this week. From the beginning of August, we have observed a huge surge of malicious spam which far exceeds anything we have seen over the past two years," the company said on its blog.
"This is an epic amount of malicious spam. After multiple recent botnet takedowns, cyber criminal groups remain resilient, clearly looking to build their botnets and distribute more fake AV in the process. It seems spammers have returned from a holiday break and are enthusiastically back to work," the blog added.
Malicious spam emails used traditional tricks such as fake messages about credit cards being blocked, hotel bills and UPS deliveries to lure people in, M86 added.
Recently M86’s CEO John Vigouroux told CBR security companies were doing a "miserable job" of protecting their customers by relying on out of date technologies that are not able to keep up with modern threats.
"Clearly the industry is doing a miserable job," he said, "but at the same time it’s saying ‘I’m McAfee, Sophos, Symantec: use me and you’re safe’. Clearly that’s not working so well. The industry is doing something wrong."
