Medium severity · published Feb 26, 2021
CVE-2021-21330
aiohttp is an asynchronous HTTP client/server framework for asyncio and Python
6.1
CVSS
1.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.9% · higher than 80% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AI
Aiohttp · Aiohttp
before 3.7.4 · source: NVD
DL
Debian Linux · Debian
10.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21330
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21330
Third Party Advisory
https://github.com/aio-libs/aiohttp/blob/master/CHANGES.rst#374-2021-02-25
Patch
https://github.com/aio-libs/aiohttp/commit/2545222a3853e31ace15d87ae0e2effb7da0c96b
Third Party Advisory
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-v6wp-4m6f-gcjg
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FU7ENI54JNEK3PHEFGCE46DGMFNTVU6L/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JN3V7CZJRT4QFCVXB6LDPCJH7NAOFCA5/
Product
https://pypi.org/project/aiohttp/
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