# Event Loop Blocking + Lazy images
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In [**this exploit**](https://gist.github.com/aszx87410/155f8110e667bae3d10a36862870ba45), [**@aszx87410**](https://twitter.com/aszx87410) mixes the **lazy image side channel** technique through a HTML injection with kind of **event loop blocking technique** to leak chars.
This is a **different exploit for the CTF chall** that was already commented in the following page. take a look for more info about the challenge:
{% content-ref url="connection-pool-example.md" %}
[connection-pool-example.md](connection-pool-example.md)
{% endcontent-ref %}
The idea behind this exploit is:
* The posts are loaded alphabetically
* An **attacker** can **inject** a **post** starting with **"A"**, then some **HTML tag** (like a big **`