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Blacksun4

By Amr

level4 is an installation of Apache and PHP with an introduced heap vulnerability.

Estimated reading time: 0 minutes

Table of Contents

Source: This content is aggregated from overthewire (MIT). Visit the original repository for the latest version.

level4 is an installation of Apache and PHP with an introduced heap vulnerability.

The introduced vulnerability is as follows:

Thanks to orix for the introduced code snippet

The document root is in /levels/level4/htdocs, you’ll need to put your php code there and call it via the webserver on port 55555.

Note: that if you’re executing a shell, it can’t be /bin/sh or /bin/bash, oh, and the apache process can’t access the /etc/pass directory :P

Binary information

Stack smashing protection (SSP): Enabled
Postition Independent Executable (PIE): Enabled
Address space layout randomisation (ASLR): Enabled
Non-executable pages: None / disabled
Location: 127.0.0.1:55555