    readUInt64BE: (behavior) => {
      if (!buffer || pos + 7 >= buffer.length)
        return;
      switch (behavior) {
        case 'always':
          return BigInt(`0x${buffer.hexSlice(pos, pos += 8)}`);
        case 'maybe':
          if (buffer[pos] > 0x1F)
            return BigInt(`0x${buffer.hexSlice(pos, pos += 8)}`);
          // FALLTHROUGH
        default:
          return (buffer[pos++] * 72057594037927940)
                 + (buffer[pos++] * 281474976710656)
                 + (buffer[pos++] * 1099511627776)
                 + (buffer[pos++] * 4294967296)
                 + (buffer[pos++] * 16777216)
                 + (buffer[pos++] * 65536)
                 + (buffer[pos++] * 256)
                 + buffer[pos++];
      }
    },
The software constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.