Django-piston and Django-tastypie do not properly deserialize YAML data

The vulnerability lies in the emitters.py file, specifically in how Django Piston handles YAML data. An attacker can craft malicious YAML input that, when deserialized using yaml.load, will execute arbitrary Python code on the server. This allows for complete system compromise, including data exfiltration, modification, and the installation of malware. The blast radius is significant, potentially affecting all users of the application if the API is exposed. This vulnerability shares similarities with other deserialization flaws, where untrusted data is processed without proper sanitization, leading to code execution. The potential for remote code execution makes this a high-priority vulnerability.

Applications built using Django Piston for API development are at risk. This includes web applications, mobile backends, and other systems that rely on Django Piston for data serialization and API endpoints. Specifically, older projects that haven't been updated in several years are particularly vulnerable, as they are more likely to be running outdated versions of Django Piston.

• python / server:

Get-Process -Name python | Where-Object {$_.Path -like '*django-piston*'} | Select-Object ProcessId, Path

• python / server:

Get-ChildItem -Path 'C:\Program Files\Python\Lib\site-packages\django_piston' -Recurse -Filter 'emitters.py'

• generic web: Inspect API endpoints for YAML data handling. Check access logs for requests containing YAML payloads. • generic web: Use curl to test API endpoints with crafted YAML payloads. Monitor for unusual server behavior or error messages.

1. 2011-07-14Discovery

   discovery

2. 2018-07-23Disclosure

   disclosure

3. 2018-07-23Patch

   patch

1. Veröffentlicht2018-07-23
2. Geändert2024-09-16
3. EPSS aktualisiert2026-04-02

The primary mitigation is to upgrade Django Piston to version 0.2.2.1 or later, which addresses the vulnerability. If upgrading is not immediately feasible, consider implementing input validation and sanitization on all YAML data received through the API. Web application firewalls (WAFs) can be configured to block requests containing suspicious YAML payloads. Restrict access to the API endpoints to trusted sources only. Monitor API logs for unusual activity or attempts to exploit the vulnerability. After upgrading, confirm the fix by attempting to load a known malicious YAML payload and verifying that it is rejected or handled safely.