Vulnerability in Aio-libs Aiohttp

CVE-2026-34514

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in aiohttp could use this to inject extra headers or similar exploits. This issue…

EPSS: 0.000 (3.1th percentile) — read the EPSS interpretation.

Affected products

Aio-libs Aiohttp — versions < 3.13.4

Weakness classification (CWE)

CWE-113 — HTTP Response Splitting

References

https://github.com/aio-libs/aiohttp/security/advisories/GHSA-2vrm-gr82-f7m5 (x_refsource_CONFIRM)
https://github.com/aio-libs/aiohttp/commit/9a6ada97e2c6cf1ce31727c6c9fcea17c21f6f06 (x_refsource_MISC)
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 (x_refsource_MISC)