Extraterrestrial Persistence

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

Description

There is a rumor that aliens have developed a persistence mechanism that is impossible to detect. After investigating her recently compromised Linux server, Pandora found a possible sample of this mechanism. Can you analyze it and find out how they install their persistence?

Solution Approach

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

Steps

1. Unzipping the file shall resulting a bashscript file.

THE SCRIPT

1. Notice there's a base64 and the decoded value stored to /usr/lib/systemd/system/service.service. Let's grab the base64 text and decode it.

2. 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.