--- title: TryHackMe — Guided Pentest: Infrastructure | Full... description: A step-by-step walkthrough of TryHackMe's 'Guided Pentest: Infrastructure' room, covering the full penetration testing workflow: Nmap enumeration, identifying... canonical: https://daily.dev/posts/tryhackme-guided-pentest-infrastructure-full-walkthrough-d3y3lmysw twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: TryHackMe — Guided Pentest: Infrastructure | Full Walkthrough | daily.dev og:description: A step-by-step walkthrough of TryHackMe's 'Guided Pentest: Infrastructure' room, covering the full penetration testing workflow: Nmap enumeration, identifying... og:url: https://daily.dev/posts/tryhackme-guided-pentest-infrastructure-full-walkthrough-d3y3lmysw og:image: https://api.daily.dev/og/posts/d3y3LmysW.png og:image:alt: TryHackMe — Guided Pentest: Infrastructure | Full Walkthrough og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # TryHackMe — Guided Pentest: Infrastructure | Full Walkthrough **[InfoSec Write-ups](https://daily.dev/sources/infosecwriteups)** · 7 min read · 4 upvotes · 0 comments ## Summary A step-by-step walkthrough of TryHackMe's 'Guided Pentest: Infrastructure' room, covering the full penetration testing workflow: Nmap enumeration, identifying UnrealIRCd 3.2.8.1 as vulnerable, exploiting its known backdoor via Metasploit to gain a shell as 'webmaster', discovering a plaintext root password in /etc/password.txt, escalating to root over SSH, and drafting a sample vulnerability report with remediation advice. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do you exploit the UnrealIRCd 3.2.8.1 backdoor with Metasploit? Use the Metasploit module exploit/unix/irc/unreal_ircd_3281_backdoor, set RHOSTS to the target IP, LHOST to your attacker IP, RPORT to 6667, and choose the payload/cmd/unix/reverse payload, then run exploit. This triggers the pre-inserted backdoor in UnrealIRCd 3.2.8.1's source code, opening a reverse shell as the webmaster user without needing credentials. _Practicing exploit workflows like this gets easier when daily.dev surfaces trusted pentest and security writeups in one place._ ### Why is UnrealIRCd version 3.2.8.1 considered dangerous? UnrealIRCd 3.2.8.1 shipped with a backdoor secretly inserted into its official source code download, allowing remote attackers to execute arbitrary commands on any server running it. This is a classic supply chain compromise: the vulnerability isn't a bug but a deliberately planted command execution backdoor, exploitable directly via a known Metasploit module. _Tracking supply chain risks in specific software versions is easier when daily.dev keeps security research within reach._ ### What Nmap flags should I use for a quick but thorough service enumeration scan? Run nmap -sC -sV -T5 -oN output.txt against the target. The -sC flag runs Nmap's default scripts for banners and auth details, -sV detects service versions, -T5 sets aggressive scan timing, and -oN saves results to a file for later reference in a report. _Refining recon commands like this stays practical when daily.dev keeps hands-on security tutorials close at hand._ ## Similar posts on daily.dev - [TryHackMe — Blog CTF \| Full Write-Up](https://daily.dev/posts/tryhackme-blog-ctf-full-write-up-clubifl5s) · InfoSec Write-ups · 0 upvotes · 0 comments - [Publisher: TryHackMe CTF Walkthrough](https://daily.dev/posts/publisher-tryhackme-ctf-walkthrough-ksu6i6grg) · InfoSec Write-ups · 0 upvotes · 0 comments - [Lian\_Yu — TryHackMe Walkthrough](https://daily.dev/posts/lian-yu-tryhackme-walkthrough-onjz1q3mj) · InfoSec Write-ups · 0 upvotes · 0 comments - [TryHackMe: Room 404 Walkthrough \(Hacker’s Holiday Challenge\)](https://daily.dev/posts/tryhackme-room-404-walkthrough-hacker-s-holiday-challenge--np3fgcqtz) · InfoSec Write-ups · 0 upvotes · 0 comments - [TryHackMe — Simple CTF: The Note That Gave Everything Away](https://daily.dev/posts/tryhackme-simple-ctf-the-note-that-gave-everything-away-8aiksehw2) · InfoSec Write-ups · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#linux](https://daily.dev/tags/linux) [View this post on daily.dev](https://daily.dev/posts/tryhackme-guided-pentest-infrastructure-full-walkthrough-d3y3lmysw) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"TryHackMe — Guided Pentest: Infrastructure | Full Walkthrough","url":"https://daily.dev/posts/tryhackme-guided-pentest-infrastructure-full-walkthrough-d3y3lmysw","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/tryhackme-guided-pentest-infrastructure-full-walkthrough-d3y3lmysw"},"datePublished":"2026-08-17T21:35:19.269Z","dateModified":"2026-09-13T21:34:31.353Z","description":"A step-by-step walkthrough of TryHackMe's 'Guided Pentest: Infrastructure' room, covering the full penetration testing workflow: Nmap enumeration, identifying...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/dc637f365d3c430ec84aec132a23a3d0?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/dc637f365d3c430ec84aec132a23a3d0?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"InfoSec Write-ups","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"InfoSec Write-ups","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/f0dc21b5bbfd46fda36f7b4b53dd1705","url":"https://daily.dev/sources/infosecwriteups"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/tryhackme-guided-pentest-infrastructure-full-walkthrough-d3y3lmysw","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":4},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"security,linux","timeRequired":"PT7M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"InfoSec Write-ups","item":"https://daily.dev/sources/infosecwriteups"},{"@type":"ListItem","position":3,"name":"TryHackMe — Guided Pentest: Infrastructure | Full Walkthrough"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/tryhackme-guided-pentest-infrastructure-full-walkthrough-d3y3lmysw#faq","mainEntity":[{"@type":"Question","name":"How do you exploit the UnrealIRCd 3.2.8.1 backdoor with Metasploit?","acceptedAnswer":{"@type":"Answer","text":"Use the Metasploit module exploit/unix/irc/unreal_ircd_3281_backdoor, set RHOSTS to the target IP, LHOST to your attacker IP, RPORT to 6667, and choose the payload/cmd/unix/reverse payload, then run exploit. 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