CVE-2021-21330
mediumpriority · track · 25EPSS 0.019 · 80 %ileEURUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.1–6.1
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (13)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-v6wp-4m6f-gcjg`aiohttp` Open Redirect vulnerability (`normalize_path_middleware` middleware)2021-02-26ghsa · osvUS
### Impact 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. ### Patches This security problem has been fixed in v3.7.4. Upgrade your dependency as follows: [`pip install aiohttp >= 3.7.4`] ### Workarounds If upgrading is not an option for you, a workaround can be to avoid using `aiohttp.web_middlewares.normalize_path_middleware` in your applications. ### References * [aiohttp @ PyPI] * [GHSA-v6wp-4m6f-gcjg] * [OWASP page on open redirects] ### For more information If you have any questions or comments about this advisory: * Open an issue in the [aiohttp repo](https://github.com/aio-libs/aiohttp/issues/new/choose) * Email us at wk+aio-libs-security@sydorenko.org.ua and/or andrew.svetlov+aio-libs-security@gmail.com Credit: [Jelmer Vernooij] and [Beast Glatisant]. [aiohttp @ PyPI]: https://pypi.org/p/aiohttp [`pip install aiohttp >= 3.7.4`]: https://pypi.org/project/aiohttp/3.7.4/ [GHSA-v6wp-4m6f-gcjg]: https://github.com/aio-libs/aiohttp/security/advisories/GHSA-v6wp-4m6f-gcjg [OWASP page on open redirects]: https://cheatsheetseries.owasp.org/cheatsheets/Unvalidated_Redirects_and_Forwards_Cheat_Sheet.html [Jelmer Vernooij]: https://jelmer.uk [Beast Glatisant]: https://github.com/g147
- PYSEC-2021-762021-02-26vendor · osvUS
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.
also known as (7)
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sources
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references (32)
External citations — patches, advisories, analysis.
- https://github.com/aio-libs/aiocnnvd
- https://github.com/aio-libs/aiohttp/security/advisories/GHSA-v6wp-4m6f-gcjgPatchcnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FU7ENI54JNEK3PHEFGCE46DGMFNTVU6L/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JN3V7CZJRT4QFCVXB6LDPCJH7NAOFCA5/cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-21330cnnvd
- https://packetstormsecurity.com/files/164991/Red-Hat-Security-Advisory-2021-4702-01.htmlcnnvd
- https://packetstormsecurity.com/files/168060/Gentoo-Linux-Security-Advisory-202208-19.htmlcnnvd
- https://pypi.org/project/aiocnnvd
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