So the author charitably calls the 2025 vulnerability a "login bypass", but it's much worse than that. The firmware included a "datetime-based password" mechanism: a built-in backdoor password, like it's the 90s again.

The original researcher published about this in August of this year [1], a year after reporting it, titling the report "Defrost the Food", which the attackers apparently took to be a good suggestion.

As the firmware is open for anyone to download [2], blurring the affected function seems more like an invitation to find out more. I know I was curious when the news about the fridges in France broke. The function's actually called "check_code_of_the_day", and this is the implementation:

  uchar check_code_of_the_day(LPCTSTR pass) {
    uchar uVar1;
    LPCTSTR pass_local;
    DATE_STRUCT date;
    INT32 tothex;
    INT32 hex;
    UTF8_STR buff;

    Get_syst_current_tds(&date);
    ftext_s(buff,0x1ff,"%02d%02d%02d%02d",date.month,date.day,date.year,date.month);
    sscanf(buff,"%lx",&tothex);
    ftext_s(buff,0x1ff,,date.day);
    sscanf(buff,"%lx",&hex);
    tothex = __aeabi_idiv(tothex,hex);
    ftext_s(buff,0x1ff,"%05ld",tothex % 100000);
    if ((((*pass == buff[0]) && (pass[1] == buff[1])) && (pass[2] == buff[2])) &&
       ((pass[3] == buff[3] && (pass[4] == buff[4])))) {
      uVar1 = '\x01';
    }
    else {
      uVar1 = '\0';
    }
    return uVar1;
  }

[2] https://www.danfoss.com/en-us/service-and-support/downloads/...