config.py in pystemon before 2021-02-13 allows code execution via YAML deserialization because SafeLoader and safe_load are not used.
Weakness
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Pystemon |
Pystemon_project |
* |
2021-02-13 (excluding) |
Potential Mitigations
- Make fields transient to protect them from deserialization.
- An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.
References