CVE-2026-54275
High
Description
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.
SeverityHigh
CVSS7.5
Exploit probability—
ProductAiohttp
PublishedJun 22, 2026
First seenJun 22, 2026
Weakness typeCWE-297CWE-297
How to fix
Update
- aiohttp aiohttp3.14.1 or later
- aiohttp3.14.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| aiohttp aiohttp | v < 3.14.1 | 3.14.1 |
| aiohttpPyPI | v < 3.14.1 | 3.14.1 |
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