0ld is g0ld

Platform: HackTheBox | Category: OSINT | Difficulty: Easy | Author: D3v0o0Nu11 | Date: 2026-02-10

Description

Old algorithms are not a waste, but are really precious...

Solution Approach

Core idea: Identify the weakness from source review or fingerprinting first. Iterate with incremental payloads instead of guessing.

Steps

1. First, unzip the .zip file given.

2. Let's check the file type.

3. Anyway, open the pdf file.

4. Seems we need to find the password.

5. Let's use pdfcrack.

 sh read-only • copy allowed Copy
pdfcrack -w /usr/share/wordlists/rockyou.txt -f '0ld is g0ld.pdf'

1. Got the pass, use the pass now.

2. Notice there's something down there.

3. Copy it then decode it using this online tool.

4. Wrap it with HTB{}.

5. Got the flag.

Flag

REDACTED

Lessons Learned

1. Identify the weakness from source review or fingerprinting first.
2. Iterate with incremental payloads instead of guessing.
3. Reuse the same pattern in future engagements.