# CVE-2021-21330: python3-aiohttp: aiohttp is an asynchronous HTTP client/server framework for asyncio and Python

CVE-2021-21330 is fixed in python3-aiohttp on 1 platform, first by python3-aiohttp 3.0.1-1ubuntu0.1~esm1, released February 25, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-21330
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0191
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 25, 2021

## Description

aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. In aiohttp before version 3.7.4 there is an open redirect vulnerability. A maliciously crafted link to an aiohttp-based web-server could redirect the browser to a different website. It is caused by a bug in the `aiohttp.web_middlewares.normalize_path_middleware` middleware. This security problem has been fixed in 3.7.4. Upgrade your dependency using pip as follows "pip install aiohttp >= 3.7.4". If upgrading is not an option for you, a workaround can be to avoid using `aiohttp.web_middlewares.normalize_path_middleware` in your applications.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | python3-aiohttp Ubuntu 18.04.6 LTS (bionic) | 3.0.1-1ubuntu0.1~esm1 | [python3-aiohttp 3.0.1-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3-aiohttp-3.0.1-1ubuntu0.1-esm1.md) | Feb 25, 2021 |
| Linux | python3-aiohttp Ubuntu 20.04 LTS (focal) | 3.6.2-1ubuntu0.1~esm1 | [python3-aiohttp 3.6.2-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python3-aiohttp-3.6.2-1ubuntu0.1-esm1.md) | Feb 25, 2021 |

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