Your CPU has Intel Hyper-Threading Technology, which takes advantage of otherwise unused resources on each core to enhance performance.
Hyper-Threading Technology duplicates a limited set of CPU resources, such as registers, to enable each core to handle multiple threads. Modern CPUs have many different execution units in each core and not all of them may be in use by any particular program. When some of these resources are free, such as when one thread on a core is stalled, Hyper-Threading allows another thread to work on the same core.
A processor with HTT will appear to the operating system as having twice as many logical processors, but each pair of "cores" actually shares the same resources. This means that HTT is not a substitute for actual cores, although it will usually increase performance on workloads that use many threads, such as when multitasking.
Based on the specifications, your processor has two cores but can process four threads concurrently using Hyper-Threading Technology.