1. Global currency crisis: The global currency crisis is caused by factors such as unbalanced global economic development, fluctuation of foreign exchange market and investor panic, and so far there is no effective solution.

2. Commercial fraud: Commercial fraud refers to the fraudulent behavior that the commercial subject uses deception, misleading, lying and other means to harm the interests of others. Due to the continuous development of technical means, there is no effective cracking measure at present.

3. International criminal organizations: International criminal organizations refer to organizations mainly engaged in criminal activities such as drug trafficking, smuggling and kidnapping. Their actions are very hidden, so far there are no effective measures to crack them.