CVE-2026-34517

low-risk
Published 2026-04-01

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, for some multipart form fields, aiohttp read the entire field into memory before checking client_max_size. This issue has been patched in version 3.13.4.

Do I need to act?

-
0.05% chance of exploitation
EPSS score — low exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.3/10 Medium
NETWORK / LOW complexity

Affected Products (1)

Affected Vendors

Aiohttp

References (3)

Patch https://github.com/aio-libs/aiohttp/commit/cbb774f38330563422ca0c413a71021d7b944...
Release Notes https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4
Patch https://github.com/aio-libs/aiohttp/security/advisories/GHSA-3wq7-rqq7-wx6j
26
/ 100
low-risk
Severity 21/34 · High
Exploitability 0/34 · Minimal
Exposure 5/34 · Minimal