CVE-2026-54275

EUVD-2026-38312

22.06.2026, 18:16

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, the server_hostname TLS SNI check can be bypassed when an existing connection is reused. If an application makes multiple requests to the same domain, but with different per-request server_hostname parameters, then the later calls may succeed by reusing the existing connection when they should have been rejected due to the TLS SNI check. This vulnerability is fixed in 3.14.1.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	UNKNOWN				---

Awaiting analysis

This vulnerability is currently awaiting analysis.

Base Score

CVSS 3.x

EPSS Score

Percentile: Unknown

Debian Releases

Debian Product

Codename

python-aiohttp

bookworm	vulnerable
bookworm (security)	vulnerable
bullseye	vulnerable
bullseye (security)	vulnerable
forky	3.14.1-1 fixed
sid	3.14.1-1 fixed
trixie	vulnerable
trixie (security)	vulnerable

Common Weakness Enumeration

CWE-297 - Improper Validation of Certificate with Host Mismatch
The software communicates with a host that provides a certificate, but the software does not properly ensure that the certificate is actually associated with that host.

References

https://github.com/aio-libs/aiohttp/security/advisories/GHSA-4m7w-qmgq-4wj5