> For the complete documentation index, see [llms.txt](https://csbygb.gitbook.io/pentips/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://csbygb.gitbook.io/pentips/writeups/vulnmachines-writeups/vulnmachine-web-intermediate.md).

# Web Labs Intermediate

## SSTI

We end up on this page

![form](/files/FXEhhlaG4dOxPLermOqn)

* If we enter `{{` we get an exception

![Exception](/files/vDYG3THrPDdX7ho1wMWD)

* Let's find out which template it uses using James Kettle tree (see more details about this [here](https://csbygb.gitbook.io/pentips/web-pentesting/webvulns/template-injection))
* This one `{{7*7}}` evaluates

![evaluates](/files/qWj9Mp0Bz5sRVAYoQokc)

However this `{{7*'7'}}` seems to reveal that some char are filtered

![filter](/files/uRdrNQMYMgO6kkZZImPM)

If we use double quotes instead it works `{{7*"7"}}`

![double quotes](/files/DeasY0N1Smr3jeZESuGC)

According to the tree it can be Jinja2 or Twig

As we have a header leaking the Python version, the template should be Jinja2 as it is based on python

![python version](/files/jdC1xjwGUiiT9Ji02m0m)

* let's try to find the config `{{config}}`

![config](/files/luWZyPG1J5HGPUzQPwst)

We get the flag here but it seems encoded. If we use burpsuite and decode it as ASCII hex, we get the flag!

![decode](/files/w3w416JXdRkWTf2UUB8d)


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