--- title: 'USN-7612-1: Flask-CORS vulnerabilities | Ubuntu security notices' description: Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things. url: https://ubuntu.com/security/notices/USN-7612-1 --- 1. [Ubuntu Security Notices](https://ubuntu.com/security/notices) 2. USN-7612-1 --- # USN-7612-1: Flask-CORS vulnerabilities Publication date 2 July 2025 Overview Several security issues were fixed in Flask-CORS. Releases [25.04](https://ubuntu.com/security/notices?release=plucky) [24.10](https://ubuntu.com/security/notices?release=oracular) [24.04 LTS](https://ubuntu.com/security/notices?release=noble) [22.04 LTS](https://ubuntu.com/security/notices?release=jammy) [20.04 LTS](https://ubuntu.com/security/notices?release=focal) --- Open side navigation ## Packages * [python-flask-cors](https://ubuntu.com/security/cves?package=python-flask-cors) - Flask extension for handling Cross Origin Resource Sharing (CORS) ## Details It was discovered that Flask-CORS did not correctly handle certain regular expressions. A remote attacker could possibly use this issue to leak sensitive information or bypass authentication mechanisms. ([CVE-2024-6839](https://ubuntu.com/security/CVE-2024-6839)) It was discovered that Flask-CORS allowed certain CORS headers to be enabled by default. A remote attacker could possibly use this issue to leak sensitive information. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS and Ubuntu 24.10. ([CVE-2024-6221](https://ubuntu.com/security/CVE-2024-6221)) It was discovered that Flask-CORS did not correctly handle case sensitivity when matching paths. A remote attacker could possibly use this issue to leak sensitive information. ([CVE-2024-6866](https://ubuntu.com/security/CVE-2024-6866)) It was discovered that Flask-CORS did not correctly handle certain characters in URL paths. A remote attacker could possibly use this issue to... --- Show more ## Update instructions In general, a standard system update will make all the necessary changes. [Learn more about how to get the fixes.](https://ubuntu.com/security/cves/about#security) The problem can be corrected by updating your system to the following package versions: | Ubuntu Release | Package Version | | --- | --- | | 25.04 plucky | [python3-flask-cors](https://launchpad.net/ubuntu/+source/python-flask-cors) –  [5.0.0-1ubuntu0.1](https://launchpad.net/ubuntu/+source/python-flask-cors/5.0.0-1ubuntu0.1) | | | | 24.10 oracular | [python3-flask-cors](https://launchpad.net/ubuntu/+source/python-flask-cors) –  [4.0.1-1ubuntu0.1](https://launchpad.net/ubuntu/+source/python-flask-cors/4.0.1-1ubuntu0.1) | | | | 24.04 LTS noble | [python3-flask-cors](https://launchpad.net/ubuntu/+source/python-flask-cors) –  4.0.0-1ubuntu0.1~esm1   Ubuntu Pro | | | | 22.04 LTS jammy | [python3-flask-cors](https://launchpad.net/ubuntu/+source/python-flask-cors) –  [3.0.9-2ubuntu0.1](https://launchpad.net/ubuntu/+source/python-flask-cors/3.0.9-2ubuntu0.1) | | | | 20.04 LTS focal | [python3-flask-cors](https://launchpad.net/ubuntu/+source/python-flask-cors) –  3.0.8-2ubuntu0.1+esm1   Ubuntu Pro | | | --- ### Reduce your security exposure Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines. [Get Ubuntu Pro](https://ubuntu.com/pro) ## References * [CVE-2024-6866](https://ubuntu.com/security/CVE-2024-6866) * [CVE-2024-6844](https://ubuntu.com/security/CVE-2024-6844) * [CVE-2024-6839](https://ubuntu.com/security/CVE-2024-6839) * [CVE-2024-6221](https://ubuntu.com/security/CVE-2024-6221) * [CVE-2024-1681](https://ubuntu.com/security/CVE-2024-1681)