CVE-2022-40189 is a vulnerability related to Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') in the Pig Provider module of Apache Airflow. This vulnerability enables attackers to control commands executed in the task execution context even without having write access to DAG (Directed Acyclic Graph) files. The vulnerability affects Pig Provider versions prior to 4... Additionally, Apache Airflow versions prior to 2.3. might also be affected if Pig Provider is installed. To mitigate the vulnerability, one must manually install Pig Provider version 4.. on top of Airflow 2.3.+.

Details

The vulnerability occurs due to insufficient input validation when processing user-supplied data, which allows an attacker to inject arbitrary OS commands within the task execution context. The following code snippet demonstrates the vulnerability:

from airflow.providers.apache.pig.operators.pig import PigOperator
from airflow import DAG

# the following code is vulnerable to OS command injection
pig_operator = PigOperator(
    task_id='pig_command',
    pig="Run script.pig with_params '-param foo=" + userInput + "'"
)

In this example, the userInput variable is directly concatenated with the pig script command, which is executed by the PigOperator. If an attacker can control the value of userInput, they may inject arbitrary OS commands.

Exploit

An attacker can exploit this vulnerability by providing a crafted input that contains OS command injection payload. As an example, consider the following crafted input sent by an attacker:

'; rm -rf / #'

When this input is processed by the vulnerable code, it gets concatenated with the pig command as follows:

pig="Run script.pig with_params '-param foo= "'; rm -rf / #'"

After execution, this command would consequently delete all files and directories within the root directory of the affected system.

Mitigation

To get rid of this vulnerability, users must update their Pig Provider to version 4.. or later. Note that Pig Provider version 4.. can only be installed on Airflow versions 2.3. and higher. To update the module, use the following command:

pip install "apache-airflow-providers-apache-pig>=4.."

Additionally, it is essential to perform proper input validation and sanitization on user-supplied data to mitigate the risk of OS command injection.

Original references

1. Apache Airflow Pig Provider Release Notes
2. CVE-2022-40189
3. Apache Airflow Security Advisory

Conclusion

CVE-2022-40189 is a critical vulnerability that exposes Apache Airflow users to the risk of OS command injection attacks. Users are advised to update their Pig Provider to version 4.. or later and perform proper input validation on user-supplied data. Staying proactive with security updates and applying best coding practices is vital to ensure that your infrastructure remains secure against potential vulnerabilities.

Timeline

Published on: 11/22/2022 10:15:00 UTC
Last modified on: 11/29/2022 13:57:00 UTC