A new vulnerability (CVE-2024-12254) has been identified in Python that could allow a remote attacker to consume system resources, potentially leading to a denial of service (DoS) condition. This issue was discovered in the way Python handles asyncio write buffers and affects Python 3.12. Systems running Ubuntu 24.10 and Ubuntu 24.04 LTS with affected Python versions should update their installations to mitigate the risk. In this post, we will break down the details of the vulnerability, its potential impact, and the steps to update your system.
Vulnerability Details:
- Affected Versions:
- Python 3.12 running on Ubuntu 24.10 and Ubuntu 24.04 LTS.
- CVE Identifier:
- CVE-2024-12254
- Issue: The vulnerability stems from how Python handles asyncio write buffers. Specifically, Python’s asyncio framework was found to improperly manage certain write buffers, which could allow an attacker to send specially crafted network traffic. This would cause the Python process to consume excessive memory resources, potentially leading to system instability or a denial of service (DoS). The issue occurs in Python’s asynchronous programming capabilities, particularly when dealing with I/O-bound tasks that involve writing data to buffers. By exploiting this vulnerability, an attacker could force the system to consume an excessive amount of memory, which could affect performance or cause a crash.
Impact:
- Denial of Service (DoS): The primary risk of this vulnerability is a denial of service. If exploited, this vulnerability could cause the affected Python process to consume all available system memory, leading to a system crash or slow performance. This could disrupt applications or services that rely on Python for handling asynchronous tasks or network traffic.
- Resource Consumption: The exploitation of this vulnerability would result in high memory consumption, potentially bringing down critical services running on the affected systems. This could have a significant impact on environments that rely heavily on Python for web servers, data processing, or other essential tasks.
How to Protect Your System:
To address this vulnerability, it’s important to update your system to the fixed Python packages provided by the latest security update. The update will correct the way Python handles asyncio write buffers and mitigate the risk of memory consumption due to specially crafted network traffic.
Update Instructions:
The issue can be resolved by updating Python to the following versions:
- Ubuntu 24.10:
- python3.12 – 3.12.7-1ubuntu1.1
- python3.12-minimal – 3.12.7-1ubuntu1.1
- Ubuntu 24.04 LTS:
- python3.12 – 3.12.3-1ubuntu0.4
- python3.12-minimal – 3.12.3-1ubuntu0.4
A standard system update will typically apply all necessary changes, but it is always recommended to verify the updates and restart the system after installation to ensure that the new versions are running properly.
How to Update Your System:
- Update your package list:
sudo apt update - Upgrade Python packages:
sudo apt upgrade python3.12 python3.12-minimal - Restart the system or the affected services:
sudo reboot
This will install the latest security patches and fix the vulnerabilities in Python.
Conclusion:
The USN-7219-1 Python vulnerability (CVE-2024-12254) is a critical issue that can cause memory consumption and potentially lead to denial of service if exploited. Users running Python 3.12 on Ubuntu 24.10 and Ubuntu 24.04 LTS are strongly advised to update their systems as soon as possible to avoid any security risks. Applying the update will address this vulnerability and ensure that your Python-based applications and services continue to run securely.