CVE-2021-21330

Open redirect vulnerability in aiohttp

MEDIUM
6.1
CVSS Score
Published: February 26, 2021 at 02:15 AM UTC
Updated: June 17, 2026 at 03:35 AM UTC
4 products affected across 4 vendorsDebian LinuxFedoraAiohttp

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Severity
MEDIUM6.1
Exploit prediction
EPSS 2%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 3.7.4
Affected range stops below 3.7.4, so it looks safe — our inference, not a vendor statement
v < 3.7.4
Affected range stops below 3.7.4, so it looks safe — our inference, not a vendor statement

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-601

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