> 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/web/xxe/xxe-file-read-via-external-entities.md).
# XXE File Read via External Entities
XXE File Read via External Entities notes for PortSwigger Web Security Academy labs, including exploitation workflow, payload testing, Burp Suite validation, and remediation context.
### Exploiting XXE Using External Entities to Retrieve Files
Exploit a XXE vulnerability by declaring an external entity to recover the content of a file (here `/etc/passwd`) from the **Check stock** feature that parses from XML and returns unexpected values.
The feature sends XML like this:
{% code overflow="wrap" %}
```xml
2
1
```
{% endcode %}
If the numerical value of `` is replaced by a string, this value is reflected in the response (useful for operation):
```xml
test
```
1. Report an external entity in a DOCTYPE statement that points to the system file.
```xml
]>
```
2. Call this entity in the `` field that is returned by the application.
```
&myFile;
```
3. The response should then contain the content of the target file (`/etc/passwd`).
```xml
]>
&myFile;
1
```
---
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