This is the most direct method. Since the S7-300 does not typically implement account lockouts (depending on firmware revision), it is susceptible to brute-forcing.
The MMC card used by S7-300 is a standard multimedia card in a Siemens proprietary format. If you physically remove the MMC card (located behind the front door of the CPU), you can read it using a standard USB MMC card reader and low-level disk editing software.
STEP 7 Micro/ Win or STEP 7 Professional are software tools used for programming and configuring Siemens PLCs. You can use these tools to reset the S7300 PLC password. Here's how:
Three common scenarios:
In all these cases, the legitimate plant owner has the right to recover the asset. But Siemens does not offer a legitimate "backdoor" – for good security reasons. So, what can be done?