Unsanitized user input in deserialization method

• Rule ID: python_lang_deserialization_of_user_input
• Languages: python
• Source: deserialization_of_user_input.yml

Description

Deserializing data from untrusted sources, like user inputs or request parameters, without proper verification is a security risk. Attackers can embed malicious code or payloads within serialized data. When your application deserializes this data without checks, it becomes vulnerable to attacks.

Remediations

• Do not deserialize data from untrusted sources directly. This can lead to security vulnerabilities.
• Do validate and sanitize all data before deserializing it. Ensure that the data is coming from a trusted source and is in the expected format.
• Do use data formats that are purely data-oriented and not tied to a specific programming language, such as JSON or XML, for serialization and deserialization. This approach minimizes the risk of executing malicious code during deserialization.
• Do use recommended safer alternatives wherever possible. For example, instead of PyYAML's load function, use the safe_load function which limits results to simple Python objects like integers or lists.

    yaml.safe_load(some_input) # safer alternative to PyYAML load 

References

• OWASP Deserialization cheat sheet

Associated CWE

• CWE-502: Deserialization of Untrusted Data

OWASP Top 10

• A08:2021 - Software and Data Integrity Failures

Configuration

To skip this rule during a scan, use the following flag

bearer scan /path/to/your-project/ --skip-rule=python_lang_deserialization_of_user_input

To run only this rule during a scan, use the following flag

bearer scan /path/to/your-project/ --only-rule=python_lang_deserialization_of_user_input