The number of ransomware samples have grown by 127 percent in the past year, and 58 percent in Q2 2015 alone, according to the latest McAfee Threat Labs Report.
August marks the five-year anniversary of Intel's announcement that it would buy McAfee, so in addition to presenting some new data, the report includes a retrospective from Intel and McAfee thought leaders about how the current threat landscape matches their expectations from five years ago.
McAfee attributes the huge leap in ransomware samples to the quick growth of new families like CTB-Locker and CryptoWall, which the FBI said cost US citizens $18 million.
[Watch "Re-evaluating Ransomware, Without the Hype," an interview with researcher and Black Hat speaker Engin Kirda.]
Some ransomware specifically goes after mobile devices. Mobile malware samples were up by 17 percent, according to the report, but mobile malware infection rates ticked down slightly -- they decreased by 4 percent in North America, were unchanged in Africa, and decreased by about 1 percent in all other regions.
In their retrospective of the past five years, the report authors said that while the volume of mobile devices has grown faster than they anticipated, the evolution of "serious, broad-based attacks" on mobile devices has been happening more slowly than they expected.
Some reasons for the delay, they wrote, could be that mobile devices are not prominent attack vectors for enterprises, the value of the data residing on them is relatively low, and the common auto back-up capabilities that many mobile devices offer make it easy to clean them up and recover lost files.
With that exception, however, the authors say the attack landscape has expanded at a faster rate than they'd thought it would. "Although we expected and predicted most of this development, the rapid evolution of malware, increase in attack volume, and large scale of nation-state attacks has been surprising."
Looking forward, they wrote it's "only a matter of time," before Internet of Things devices become a common attack target -- more specifically, the data or gateway capabilities on them. McAfee researchers say the volume of IoT devices and the number of industries it's expanded into are also greater than they predicted.
The report also drilled into the topic of malware that operates in the GPU, something that got renewed attention earlier this year when Team Jellyfish released proof-of-concept code for a keylogger, a rootkit, and a remote-access Trojan that all operated in the GPU.
The appeal of GPU malware has been that it is presumably harder to detect and more persistent -- host files are deleted off the CPU, the malware persists after a warm reboot, and there aren't effective security tools that analyze GPUs.
"GPU threats are a real concern," the report statews, "But this type of attack has not reached perfect storm status."
Although reverse engineering and forensic analysis of GPU malware is much more challenging, say researchers, the process of infecting the GPU via the CPU does leave trace evidence of an attack -- even if the initial code on the CPU is deleted -- so traditional endpoint security tools operating on the CPU could detect GPU threats.