CVE-2026-54275
highpriority · track · 30EPSS 0.005 · 41 %ileEUFRRUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 2.7–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
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affected products (13)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- GHSA-4m7w-qmgq-4wj5aiohttp: TLS Server Hostname Override Is Ignored When Reusing HTTPS Connections2026-06-15ghsa · osvUS
### 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
- CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR
- PYSEC-2026-2372026-06-22vendor · osvUS
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.
also known as (7)
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sources
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references (3)
External citations — patches, advisories, analysis.
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