Verification codes

Verification code is a network verification mechanism, which is used to distinguish whether the user is a person or a computer program. It verifies whether the operator has specific human behavior characteristics by setting a series of challenges. There are various types of verification codes, including but not limited to the following: Text verification code: composed of letters and numbers, sometimes accompanied by interference lines or background noise, users need to input these characters correctly.  Image verification code: Requires users to identify specific objects or words in a picture, such as Google reCaptcha.  Logical verification code: contains mathematical calculation questions or other logical questions that users need to answer before they can pass the verification.  Audio verification code: users need to listen to audio and input the characters they hear, which is suitable for visually impaired users.  Sliding verification code: the user completes the verification by sliding operation, such as jigsaw sliding verification code.  Click on the verification code: users need to click on a specific object in the picture, such as clicking on all pictures containing traffic lights.  Rotate the verification code: users need to adjust the picture to the correct direction to complete the verification. The method of bypassing the verification code usually involves some security loopholes, such as: Null bypass of verification code: By clearing the verification code field, the server may not verify the verification code and allow brute force cracking.  Front-end verification+invalid verification: If the verification code is only verified at the front end, the verification can be bypassed.  Controllable verification code: If the verification code appears in the response package or source code in plaintext or weak encryption, you can use this to crack it violently. There are laws of captcha: If there are laws of captcha generation, you can predict captcha through analysis.  CAPTCHA Blasting: Explode CAPTCHA by traversing all possible CAPTCHA combinations. Verification code reuse: If the verification code can be reused, it can be directly cracked violently. However, it should be noted that bypassing the verification code may violate the terms of service or laws and regulations, so this information is for reference only and should not be used for illegal purposes. The correct way is to strengthen the security of verification code, for example, by increasing the complexity of verification code, limiting the number of inputs, introducing behavior analysis and other methods to improve security. At the same time, protect personal information and don't disclose the verification code to others to prevent potential security risks.