High
python-aiohttp — security advisory
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.
- Products
- python-aiohttp
- Affected versions
- 0.17.2-1, 0.17.4-1, 0.17.4-1build1, 0.20.2-1, 0.20.2-1ubuntu0.1~esm1, 2.2.3-1build1, 2.2.3-2, 2.3.6-1, 3.0.1-1, 3.0.1-1ubuntu0.1~esm1, 3.0.1-1ubuntu0.1~esm4, 3.0.1-1ubuntu0.1~esm5, 3.0.1-1ubuntu0.1~esm6, 3.0.1-1ubuntu0.1~esm7, 3.10.11-1build1, 3.11.16-1, 3.11.16-1ubuntu0.1, 3.13.1-1, 3.13.3-3, 3.13.3-3ubuntu1, 3.13.3-3ubuntu1+esm1, 3.14.1-4, 3.14.1-5, 3.14.3-1, 3.5.4-1, 3.5.4-1build1, 3.6.1-1, 3.6.2-1, 3.6.2-1build1, 3.6.2-1ubuntu0.1~esm1, 3.6.2-1ubuntu1, 3.6.2-1ubuntu1+esm1, 3.6.2-1ubuntu1+esm3, 3.6.2-1ubuntu1+esm4, 3.6.2-1ubuntu1+esm5, 3.6.2-1ubuntu1+esm6, 3.7.4-1, 3.7.4-1build2, 3.8.1-3, 3.8.1-4, 3.8.1-4build1, 3.8.1-4ubuntu0.2, 3.8.1-4ubuntu0.2+esm1, 3.8.1-4ubuntu0.2+esm2, 3.8.1-4ubuntu0.2+esm3, 3.8.4-1, 3.9.1-1, 3.9.1-1build1, 3.9.1-1ubuntu0.1, 3.9.1-1ubuntu0.1+esm1, 3.9.1-1ubuntu0.1+esm2, 3.9.1-1ubuntu0.1+esm3
- Fixed versions
- Not specified
- CVEs
- CVE-2026-54275
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:45 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-54275
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: Not specified
Complete source record
{
"id": "2f7a1171710f637f4f60886ffd4499801353834e2fb3a186b8b8887601ecf441",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-54275",
"method": "structured",
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"summary": "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.",
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],
"modified": "2026-10-17T12:59:03.915889961Z",
"provider": "osv",
"upstream": [
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],
"references": [
"https://ubuntu.com/security/CVE-2026-54275",
"https://www.cve.org/CVERecord?id=CVE-2026-54275",
"https://github.com/aio-libs/aiohttp/security/advisories/GHSA-4m7w-qmgq-4wj5"
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],
"security_relevant": true,
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},
"source_id": "core-osv",
"document_id": 359251,
"published_at": "2026-06-22T18:16:00+00:00"
}