Footprinting EASY

HTB

company Inlanefreight Ltd first server is an internal DNS server our client wants to know what information we can get out of these services and how this information could be used against its infrastructure our client has made it clear that it is forbidden to attack the services aggressively using exploits, as these services are in production. our teammates have found the following credentials “ceil:qwer1234”, company’s employees were talking about SSH keys on a forum. The administrators have stored a flag.txt file on this server to track our progress and measure success. Fully enumerate the target and submit the contents of this file as proof.

FTP 2121 and 21 confirmed creds work but limited visibility - extended passive mode - need to investigate

┌─[eu-academy-3]─[10.10.14.71]─[htb-ac-1746824@htb-bvr8ch40jz]─[~] └──╼ [★]$ nmap 10.129.42.195 -sSVC Starting Nmap 7.94SVN ( https://nmap.org ) at 2026-01-12 12:20 CST Stats: 0:01:25 elapsed; 0 hosts completed (1 up), 1 undergoing Service Scan Service scan Timing: About 75.00% done; ETC: 12:22 (0:00:27 remaining) Stats: 0:01:40 elapsed; 0 hosts completed (1 up), 1 undergoing Service Scan Service scan Timing: About 75.00% done; ETC: 12:22 (0:00:32 remaining) Nmap scan report for 10.129.42.195 Host is up (0.057s latency). Not shown: 996 closed tcp ports (reset) PORT STATE SERVICE VERSION 21/tcp open ftp | fingerprint-strings: | GenericLines: | 220 ProFTPD Server (ftp.int.inlanefreight.htb) [10.129.42.195] | Invalid command: try being more creative |_ Invalid command: try being more creative 22/tcp open ssh OpenSSH 8.2p1 Ubuntu 4ubuntu0.2 (Ubuntu Linux; protocol 2.0) | ssh-hostkey: | 3072 3f:4c:8f:10:f1:ae:be:cd:31:24:7c:a1:4e:ab:84:6d (RSA) | 256 7b:30:37:67:50:b9:ad:91:c0:8f:f7:02:78:3b:7c:02 (ECDSA) |_ 256 88:9e:0e:07:fe:ca:d0:5c:60:ab:cf:10:99:cd:6c:a7 (ED25519) 53/tcp open domain ISC BIND 9.16.1 (Ubuntu Linux) | dns-nsid: |_ bind.version: 9.16.1-Ubuntu 2121/tcp open ccproxy-ftp? | fingerprint-strings: | GenericLines: | 220 ProFTPD Server (Ceil’s FTP) [10.129.42.195] | Invalid command: try being more creative |_ Invalid command: try being more creative 2 services unrecognized despite returning data. If you know the service/version, please submit the following fingerprints at https://nmap.org/cgi-bin/submit.cgi?new-service : ==============NEXT SERVICE FINGERPRINT (SUBMIT INDIVIDUALLY)============== SF-Port21-TCP:V=7.94SVN%I=7%D=1/12%Time=69653B7D%P=x86_64-pc-linux-gnu%r(G SF:enericLines,9C,”220\x20ProFTPD\x20Server\x20(ftp.int.inlanefreight. SF:htb)\x20[10.129.42.195]\r\n500\x20Invalid\x20command:\x20try\x20b SF:eing\x20more\x20creative\r\n500\x20Invalid\x20command:\x20try\x20being
SF:x20more\x20creative\r\n”); ==============NEXT SERVICE FINGERPRINT (SUBMIT INDIVIDUALLY)============== SF-Port2121-TCP:V=7.94SVN%I=7%D=1/12%Time=69653B7D%P=x86_64-pc-linux-gnu%r SF:(GenericLines,8D,”220\x20ProFTPD\x20Server\x20(Ceil’s\x20FTP)\x20[10 SF:.129.42.195]\r\n500\x20Invalid\x20command:\x20try\x20being\x20more
SF:x20creative\r\n500\x20Invalid\x20command:\x20try\x20being\x20more\x20cr SF:eative\r\n”); Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ . Nmap done: 1 IP address (1 host up) scanned in 210.68 seconds

DNS enumerated

─[eu-academy-3]─[10.10.14.71]─[htb-ac-1746824@htb-bvr8ch40jz]─[~] └──╼ [★]$ dig axfr inlanefreight.htb @10.129.42.195

; «» DiG 9.18.33-1~deb12u2-Debian «» axfr inlanefreight.htb @10.129.42.195 ;; global options: +cmd inlanefreight.htb. 604800 IN SOA inlanefreight.htb. root.inlanefreight.htb. 2 604800 86400 2419200 604800 inlanefreight.htb. 604800 IN TXT “MS=ms97310371” inlanefreight.htb. 604800 IN TXT “atlassian-domain-verification=t1rKCy68JFszSdCKVpw64A1QksWdXuYFUeSXKU” inlanefreight.htb. 604800 IN TXT “v=spf1 include:mailgun.org include:_spf.google.com include:spf.protection.outlook.com include:_spf.atlassian.net ip4:10.129.124.8 ip4:10.129.127.2 ip4:10.129.42.106 ~all” inlanefreight.htb. 604800 IN NS ns.inlanefreight.htb. app.inlanefreight.htb. 604800 IN A 10.129.18.15 internal.inlanefreight.htb. 604800 IN A 10.129.1.6 mail1.inlanefreight.htb. 604800 IN A 10.129.18.201 ns.inlanefreight.htb. 604800 IN A 10.129.34.136 inlanefreight.htb. 604800 IN SOA inlanefreight.htb. root.inlanefreight.htb. 2 604800 86400 2419200 604800 ;; Query time: 49 msec ;; SERVER: 10.129.42.195#53(10.129.42.195) (TCP) ;; WHEN: Mon Jan 12 12:35:45 CST 2026 ;; XFR size: 10 records (messages 1, bytes 540)

┌─[eu-academy-3]─[10.10.14.71]─[htb-ac-1746824@htb-bvr8ch40jz]─[~] └──╼ [★]$ ssh ceil@10.129.42.195 The authenticity of host ‘10.129.42.195 (10.129.42.195)’ can’t be established. ED25519 key fingerprint is SHA256:AtNYHXCA7dVpi58LB+uuPe9xvc2lJwA6y7q82kZoBNM. This key is not known by any other names. Are you sure you want to continue connecting (yes/no/[fingerprint])? yes Warning: Permanently added ‘10.129.42.195’ (ED25519) to the list of known hosts. ceil@10.129.42.195: Permission denied (publickey). ┌─[eu-academy-3]─[10.10.14.71]─[htb-ac-1746824@htb-bvr8ch40jz]─[~]

Found the issue! - it was the public key i was looking for into ftp server but i didnt use the right flag for ls - should have used ls -la to see the .ssh and obtasin the public key which was id_rsa Once i got this - exfiltrated public key and used this to log into ssh - once in via SSH - used cd .. to get back into home folder and find flag folder which contained the flag.txt file.

← Back to HTB Labs