September 12, 2026
ADVANCED NMAP
High-Port Reconnaissance & Flag Discovery
By Sourabh Jala
2 min read
OBJECTIVE Perform a comprehensive Nmap scan against the assigned lab target, enumerate services and higher ports, use Nmap scripts/banner information, and identify the flag.
1. Objective & Scope
The task requires an advanced Nmap scan of the TryHackMe target and identification of the flag from higher ports using Nmap scripts or banner/fingerprint information.
2. Initial Connectivity Verification
Before enumeration, the target was checked from the Kali Linux machine. The original evidence shows successful ICMP replies from 192.168.186.129, confirming that the target was reachable.
3. Advanced Nmap Scan
sudo nmap -p- -sS -sV -O -A — script vuln -T4 -v 192.168.186.129
The command performs full TCP port enumeration and adds SYN scanning, service/version detection, OS detection, aggressive detection, vulnerability-oriented NSE scripts, faster timing, and verbose output.
4. Enumerated Services
The scan output shows seven detected TCP services. The important discovery for the challenge is the high-numbered TCP/65534 service.
5. High-Port Flag Discovery
Reviewing the high-port output revealed the challenge flag in the Nmap fingerprint/script results. The original evidence clearly displays the flag associated with the TCP/65534 service.
FLAG{HIGH_PORT_RECON_SUCCESS}
6. TryHackMe Verification
The discovered flag was entered into the TryHackMe lab question. The supplied evidence shows the answer marked as correct.
7. Methodology
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Connect the TryHackMe target to the Kali Linux environment.
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Verify reachability of 192.168.186.129.
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Scan the complete TCP port range.
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Enumerate service names and versions.
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Attempt OS and aggressive fingerprinting.
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Run the vulnerability-oriented NSE script category.
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Review higher-numbered ports, particularly TCP/65534.
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Inspect the Nmap output for banner/fingerprint information containing the flag.
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Submit the flag to the TryHackMe room and verify the result.
8. Key Takeaways
Full-port enumeration can reveal services that a default/common-port scan may miss.
Service and version detection provides useful context for interpreting exposed services.
NSE scripts can add reconnaissance and vulnerability-oriented information to a scan.
High-numbered ports should not be ignored during an authorized assessment.
The TCP/65534 finding was the decisive clue for this lab.
9. Conclusion
The advanced Nmap workflow successfully completed the lab objective. The scan identified multiple open services and, importantly, the high-numbered port 65534. The associated Nmap output exposed the required flag, which was then successfully submitted to the TryHackMe lab.