High
Security advisory
Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions of Envoy a crash occurs when configured for :ref:`upstream tunneling ` and the downstream connection disconnects while the the upstream connection or http/2 stream is still being established. There are no workarounds for this issue. Users are advised to upgrade.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-43826
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 13:02 UTC · Revision 1
Source evidence
Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions of Envoy a crash occurs when configured for :ref:`upstream tunneling ` and the downstream connection disconnects while the the upstream connection or http/2 stream is still being established. There are no workarounds for this issue. Users are advised to upgrade.
osv:CVE-2021-43826
Complete source record
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"url": "https://osv.dev/vulnerability/CVE-2021-43826",
"method": "structured",
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"title": "CVE-2021-43826",
"summary": "Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions of Envoy a crash occurs when configured for :ref:`upstream tunneling ` and the downstream connection disconnects while the the upstream connection or http/2 stream is still being established. There are no workarounds for this issue. Users are advised to upgrade.",
"evidence": "osv:CVE-2021-43826",
"products": [],
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"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
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},
"source": "https://github.com/envoyproxy/envoy/commit/4aaf9593152c6996b9da384c8918e9ad4f0abd4d",
"target": {
"file": "source/common/conn_pool/conn_pool_base.cc"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
}
],
"vanir_signatures_modified": "2026-10-20T14:32:29Z"
}
}
],
"modified": "2026-10-20T14:32:29.639105076Z",
"provider": "osv",
"references": [
"https://github.com/envoyproxy/envoy/security/advisories/GHSA-cmx3-fvgf-83mf",
"https://github.com/envoyproxy/envoy/commit/ce0ae309057a216aba031aff81c445c90c6ef145"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-43826",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 389710,
"published_at": "2022-02-22T23:15:10.957+00:00"
}