CVE-2023-37276
aiohttp.web.Application vulnerable to HTTP request smuggling via llhttp HTTP request parser
Description
aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. aiohttp v3.8.4 and earlier are bundled with llhttp v6.0.6. Vulnerable code is used by aiohttp for its HTTP request parser when available which is the default case when installing from a wheel. This vulnerability only affects users of aiohttp as an HTTP server (ie `aiohttp.Application`), you are not affected by this vulnerability if you are using aiohttp as an HTTP client library (ie `aiohttp.ClientSession`). Sending a crafted HTTP request will cause the server to misinterpret one of the HTTP header values leading to HTTP request smuggling. This issue has been addressed in version 3.8.5. Users are advised to upgrade. Users unable to upgrade can reinstall aiohttp using `AIOHTTP_NO_EXTENSIONS=1` as an environment variable to disable the llhttp HTTP request parser implementation. The pure Python implementation isn't vulnerable.
How to fix CVE-2023-37276
To remediate CVE-2023-37276, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 3.8.5 or later
- —upgrade to 3.8.5 or later
Is CVE-2023-37276 being exploited?
Moderate — EPSS is 6.1%. Track this CVE but it's not at the top of the prioritisation list.
Affected packages (3)
- from 0
- from 0, < 3.8.5
- from 0, < 3.8.5
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |