Hack The Box Explore user-flag

🎯 Objective

Capture at least one user flag per day. This entry documents a box where initial scans missed the path to user, followed by a revised approach that led to credentials and the flag.

🧭 Scope & Context

• Target: HTB machine (IP redacted in notes)
• Goal: Obtain user flag
• Approach: Recon → Enumeration/Research → Exploitation → Post-Exfil
• Caveat: Filesystem didn’t look like standard Linux; final flag was found under an sdcard-style path.

🧰 Toolkit

• nmap for network recon
• Browser + research (Exploit-DB)
• Basic file retrieval tools (curl, wget)
• SSH client

🔎 Recon (Nmap)

1) Initial scan (too “lazy”) – missed the path

Lesson: the quick defaults didn’t reveal everything useful.

2) Follow-up scan (more effective)

Example thorough scan used

nmap -sC -sV -p- -T4 -oA full_scan <TARGET>

🧵 Enumeration & Research

• A few uncommon services were exposed.
• After searching multiple sources, found a promising Exploit‑DB reference that fit the target’s service/version.

The exploit allowed listing and fetching files from the target:

Got a file downloaded as out.dat. Initially ignored it (oops). On review, it turned out to be an image with embedded creds.

🚀 Exploitation → Loot

Opened cred.jpg and found credentials:

Used them to log in over SSH:

Generic command (example):

ssh <user>@<TARGET>
# password: ******

🧭 Post-Exploitation & Flag

The target’s filesystem layout wasn’t standard Linux; after some digging, found user flag under an sdcard location:

✅ Outcome

• Access: Achieved user shell via SSH
• Flag: Retrieved from sdcard path
• Time sink: Skipping file review (out.dat) delayed progress

🧪 Commands Reference

Nmap

# Quick service discovery (may miss things)
nmap -sC -sV -T4 -oA quick <TARGET>

# Thorough — all TCP ports
nmap -sC -sV -p- -T4 -oA full_scan <TARGET>

File retrieval (generic)

# If exploit or direct path reveals files
curl -sSf -o out.dat http://<TARGET>/path/to/file
file out.dat   # identify the type
mv out.dat cred.jpg && xdg-open cred.jpg

SSH

ssh <user>@<TARGET>

💡 Lessons Learned

• Don’t skip “boring” scans: Full port sweep (-p-) early can save time.
• Validate artifacts immediately: Always inspect downloaded files (file, strings, try opening images).
• Adapt to nonstandard layouts: Some boxes mimic Android/embedded layouts; check /sdcard-like paths.
• Exploit-DB is gold: When service banners look odd, pattern-match to PoCs and read the source.

📌 Quick Checklist (for the next daily box)

• Full port scan completed (-p-)
• Service/version fingerprint saved
• Web + exploit research done
• Every downloaded artifact opened/validated
• Alternate FS paths checked (e.g., sdcard, mounted storage)
• Notes + screenshots archived