HighFix available
python-aiohttp — security advisory
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, a response with an excessive number of multipart headers may be allowed to use more memory than intended, potentially allowing a DoS vulnerability. This issue has been patched in version 3.13.4.
- Products
- python-aiohttp
- Affected versions
- 0.17.2-1, 0.17.4-1, 0.17.4-1build1, 0.20.2-1, 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, 3.10.11-1build1, 3.11.16-1, 3.11.16-1ubuntu0.1, 3.13.1-1, 3.13.3-3, 3.13.3-3ubuntu1, 3.14.1-4, 3.14.1-5, 3.14.3-1, 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, 3.8.4-1, 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
- Fixed versions
- 0.20.2-1ubuntu0.1~esm1, 3.0.1-1ubuntu0.1~esm7, 3.13.3-3ubuntu1+esm1, 3.8.1-4ubuntu0.2+esm3, 3.9.1-1ubuntu0.1+esm3
- CVEs
- CVE-2026-34516
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:00 UTC · Revision 1
Source evidence
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, a response with an excessive number of multipart headers may be allowed to use more memory than intended, potentially allowing a DoS vulnerability. This issue has been patched in version 3.13.4.
osv:UBUNTU-CVE-2026-34516
python-aiohttp
Fixed versions: 0.20.2-1ubuntu0.1~esm1
python-aiohttp
Fixed versions: 3.0.1-1ubuntu0.1~esm7
python-aiohttp
Fixed versions: 3.8.1-4ubuntu0.2+esm3
python-aiohttp
Fixed versions: 3.9.1-1ubuntu0.1+esm3
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: Not specified
python-aiohttp
Fixed versions: 3.13.3-3ubuntu1+esm1
Complete source record
{
"id": "878abd207855cafc2ad4a92bb54b48971a3900b5821a33fda6217546060f25c0",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-34516",
"method": "structured",
"payload": {
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"title": "UBUNTU-CVE-2026-34516",
"summary": "AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, a response with an excessive number of multipart headers may be allowed to use more memory than intended, potentially allowing a DoS vulnerability. This issue has been patched in version 3.13.4.",
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"value": "3.9.1-1ubuntu0.1+esm1",
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{
"value": "3.13.1-1",
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{
"value": "3.13.3-3",
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{
"value": "3.13.3-3ubuntu1",
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"aliases": [
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},
{
"type": "CVSS_V3",
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],
"modified": "2026-10-17T13:00:01.633484625Z",
"provider": "osv",
"upstream": [
"CVE-2026-34516"
],
"references": [
"https://ubuntu.com/security/CVE-2026-34516",
"https://www.cve.org/CVERecord?id=CVE-2026-34516",
"https://github.com/aio-libs/aiohttp/security/advisories/GHSA-m5qp-6w8w-w647",
"https://github.com/aio-libs/aiohttp/commit/8a74257b3804c9aac0bf644af93070f68f6c5a6f",
"https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4",
"https://ubuntu.com/security/notices/USN-8591-1"
]
},
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{
"value": "CVE-2026-34516",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/1/score"
},
"source_id": "core-osv",
"document_id": 360146,
"published_at": "2026-04-01T21:16:00+00:00"
}