Some Dahua products with Build time before December 2019 have Session ID predictable vulnerabilities. During normal user access, an attacker can use the predicted Session ID to construct a data packet to attack the device.

Dahua devices with Build time before December 2019 use strong security login mode by default, but in order to be compatible with the normal login of early devices, some devices retain the weak security login mode that users can control. If the user uses a weak security login method, an attacker can monitor the device network to intercept network packets to attack the device. So it is recommended that the user disable this login method.