The Nmap command that the tester should use to scan for ports without establishing a connection and to find version data information for services running on open ports is nmap -sS -sV -F target.company.com. This command has the following options:
-sS performs a TCP SYN scan, which is a scan technique that sends TCP packets with the SYN flag set to the target ports and analyzes the responses. A TCP SYN scan does not establish a full TCP connection, as it only completes the first step of the three-way handshake. A TCP SYN scan can stealthily scan for open ports without alerting the target system or application.
-sV performs version detection, which is a feature that probes open ports to determine the service and version information of the applications running on them. Version detection can provide useful information for identifying vulnerabilities or exploits that affect specific versions of services or applications.
-F performs a fast scan, which is a scan option that only scans the 100 most common ports according to the nmap-services file. A fast scan can speed up the scan process by avoiding scanning less likely or less interesting ports.
target.company.com specifies the domain name of the target system or network to be scanned.
The other options are not valid Nmap commands that meet the requirements of the question. Option A performs a UDP scan (-sU), which is a scan technique that sends UDP packets to the target ports and analyzes the responses. A UDP scan can scan for open ports that use UDP protocol, such as DNS, SNMP, or DHCP. However, a UDP scan does establish a connection with the target system or application, unlike a TCP SYN scan. Option C performs a TCP connect scan (-sT), which is a scan technique that sends TCP packets with the SYN flag set to the target ports and completes the three-way handshake with an ACK packet if a SYN/ACK packet is received. A TCP connect scan can scan for open ports that use TCP protocol, such as HTTP, FTP, or SSH. However, a TCP connect scan does establish a full TCP connection with the target system or application, unlike a TCP SYN scan. Option D performs an Xmas scan (-sX), which is a scan technique that sends TCP packets with the FIN, PSH, and URG flags set to the target ports and analyzes the responses. An Xmas scan can stealthily scan for open ports without alerting the target system or application, similar to a TCP SYN scan. However, option D does not perform version detection (-sV), which is one of the requirements of the question.