# CVE-2024-6839: python3-flask-cors: corydolphin/flask-cors version 4.0.1 contains an improper regex pathmatching vulnerability

CVE-2024-6839 is fixed in 2 products on 1 platform, first by python3-flask-cors 3.0.8-2ubuntu0.1+esm1, released March 20, 2025. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2024-6839
- Priority: Routine
- CVSS: 5.3 (Medium)
- EPSS: 0.0074
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 20, 2025

## Description

corydolphin/flask-cors version 4.0.1 contains an improper regex pathmatching vulnerability. The plugin prioritizes longer regex patterns overmore specific ones when matching paths, which can lead to less restrictiveCORS policies being applied to sensitive endpoints. This mismatch in regexpattern priority allows unauthorized cross-origin access to sensitive dataor functionality, potentially exposing confidential information andincreasing the risk of unauthorized actions by malicious actors.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | python-flask-cors Debian 12.15 (bookworm) | 3.0.10-2+deb12u1 | [DEBIAN-CVE-2024-6839](https://patchblox.com/security/data/fix/linux/debian-cve-2024-6839.md) | Mar 20, 2025 |
| Linux | python-flask-cors Debian 13.5 (trixie) | 6.0.1-1 | [DEBIAN-CVE-2024-6839](https://patchblox.com/security/data/fix/linux/debian-cve-2024-6839.md) | Mar 20, 2025 |
| Linux | python-flask-cors Debian 14 | 6.0.1-1 | [DEBIAN-CVE-2024-6839](https://patchblox.com/security/data/fix/linux/debian-cve-2024-6839.md) | Mar 20, 2025 |
| Linux | python3-flask-cors Ubuntu 20.04 LTS (focal) | 3.0.8-2ubuntu0.1+esm1 | [python3-flask-cors 3.0.8-2ubuntu0.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python3-flask-cors-3.0.8-2ubuntu0.1-esm1.md) | Mar 20, 2025 |
| Linux | python3-flask-cors Ubuntu 22.04.1 LTS (jammy) | 3.0.9-2ubuntu0.1 | [python3-flask-cors 3.0.9-2ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-python3-flask-cors-3.0.9-2ubuntu0.1.md) | Mar 20, 2025 |
| Linux | python3-flask-cors Ubuntu 24.04.5 LTS (noble) | 4.0.0-1ubuntu0.1~esm1 | [python3-flask-cors 4.0.0-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-python3-flask-cors-4.0.0-1ubuntu0.1-esm1.md) | Mar 20, 2025 |
| Linux | python3-flask-cors Ubuntu 24.10 (oracular) | 4.0.1-1ubuntu0.1 | [python3-flask-cors 4.0.1-1ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-python3-flask-cors-4.0.1-1ubuntu0.1.md) | Jan 16, 2026 |
| Linux | python3-flask-cors Ubuntu 25.04 (plucky) | 5.0.0-1ubuntu0.1 | [python3-flask-cors 5.0.0-1ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-python3-flask-cors-5.0.0-1ubuntu0.1.md) | Jan 16, 2026 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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