CVE-2023-47627

Request smuggling in aiohttp

aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. The HTTP parser in AIOHTTP has numerous problems with header parsing, which could lead to request smuggling. This parser is only used when AIOHTTP_NO_EXTENSIONS is enabled (or not using a prebuilt wheel). These bugs have been addressed in commit `d5c12ba89` which has been included in release version 3.8.6. Users are advised to upgrade. There are no known workarounds for these issues.

Affected

aio-libs · aiohttp

CVSS v4.0 GitHub

6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS v3.1 NVD

7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS v3.1 GITHUB

5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS

0.86% chance of exploitation in the next 30 days, 58th percentile

Published

2023-11-14

Updated

2025-11-03

Proof-of-concept exploits (1)

• aio-libs/aiohttp/security/advisories/GHSA-gfw2-4jvh-wgfg

Security advisories

• advisories/GHSA-gfw2-4jvh-wgfg
• aio-libs/aiohttp/commit/d5c12ba890557a575c313bb3017910d7616fce3d

References

• CVE Record
• NVD entry