aio-libs/aiohttp · Security
aiohttp: TLS Server Hostname Override Is Ignored When Reusing HTTPS Connections
- GHSA ID
- GHSA-4m7w-qmgq-4wj5
- CVE ID
- CVE-2026-54275
- Severity
- low
- Published
- Updated
- CVSS v4
- 2.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
Description
Summary
The server_hostname TLS SNI check can be bypassed when an existing connection is reused.
Impact
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.
Workaround
Disable keep_alive if you need to change the server_hostname check between requests.
Patch: https://github.com/aio-libs/aiohttp/commit/0ca2b6c28a25726527a8b60f25960262a91ed0e0
CWEs
- CWE-297 · Improper Validation of Certificate with Host Mismatch