CVE-2021-41773 PoC — Path traversal and file disclosure vulnerability in Apache HTTP Server 2.4.49

Source

https://github.com/zerodaywolf/CVE-2021-41773_42013

Associated Vulnerability

Title:Path traversal and file disclosure vulnerability in Apache HTTP Server 2.4.49 (CVE-2021-41773)
Description:A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 was found to be incomplete, see CVE-2021-42013.

Description

Lab setup for CVE-2021-41773 (Apache httpd 2.4.49) and CVE-2021-42013 (Apache httpd 2.4.50).

Readme

# CVE-2021-41773 and CVE-2021-42013 Lab Setup

## Setup 
```
$ git clone https://github.com/vulf/CVE-2021-41773_42013
$ cd CVE-2021-41773_42013
cd to the directory of your choice
$ docker build -t vuln_apache .
$ docker run -d vuln_apache
```
NOTE: The `httpd.conf` files are configured to be vulnerable to RCE by default. For only Path Traversal, read [this](https://github.com/vulf/CVE-2021-41773_42013#for-path-traversal-setup).

## For Path Traversal setup
* Comment the following line in `httpd.conf`
```
LoadModule cgid_module modules/mod_cgid.so
```

File Snapshot

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