The Siemens S7-200 (CPU 221, 222, 224, 226) uses a protection scheme that was historically vulnerable to "brute-force" or "recovery" utilities because the password protection was implemented at the firmware level rather than via a cryptographically secure hash.
Extract the character string displayed in the right-hand ASCII column. Step 3: Decode the S7-200 Level 3 Password
: Standard USB card readers can permanently damage or alter the proprietary file allocation table on an S7-300 MMC, rendering the card unreadable by the PLC CPU. simatic s7 200 s7 300 mmc password unlock 2006 09 11
: Use a standard laptop with an MMC reader and software like to create a raw image file of the card.
Siemens provided an official tool called Wipeout.exe (often found on the STEP 7-Micro/WIN installation CD) that resets the PLC to its "pristine status of supply," effectively removing the password by deleting the entire user program. The Siemens S7-200 (CPU 221, 222, 224, 226)
The report for , refers to a historic method for bypassing or retrieving forgotten passwords from Siemens SIMATIC S7 series PLCs, specifically focusing on the S7-300's MMC (Micro Memory Card) and the S7-200's internal memory.
Several Chinese and Russian forums (PLCforum.uz, Proview) distribute a tool called (version from 2007). When run on Windows XP with the system date set to 2006-09-11 , it can: : Use a standard laptop with an MMC
. You can recover it without deleting the program by following these steps: Create a Disk Image
If the program code is not needed, you can bypass the password by performing a factory reset.