Security advisory
An issue was discovered in Envoy 1.12.0. An untrusted remote client may send HTTP/2 requests that write to the heap outside of the request buffers when the upstream is HTTP/1. This may be used to corrupt nearby heap contents (leading to a query-of-death scenario) or may be used to bypass Envoy's access control mechanisms such as path based routing. An attacker can also modify requests from other users that happen to be proximal temporally and spatially.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2019-18801
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 10:38 UTC · Revision 1
Source evidence
An issue was discovered in Envoy 1.12.0. An untrusted remote client may send HTTP/2 requests that write to the heap outside of the request buffers when the upstream is HTTP/1. This may be used to corrupt nearby heap contents (leading to a query-of-death scenario) or may be used to bypass Envoy's access control mechanisms such as path based routing. An attacker can also modify requests from other users that happen to be proximal temporally and spatially.
osv:CVE-2019-18801
Complete source record
{
"id": "12d573b33626b20c058b657069bb90121621eaa354a0b23ad67e35ab68effc4b",
"url": "https://osv.dev/vulnerability/CVE-2019-18801",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2019-18801",
"summary": "An issue was discovered in Envoy 1.12.0. An untrusted remote client may send HTTP/2 requests that write to the heap outside of the request buffers when the upstream is HTTP/1. This may be used to corrupt nearby heap contents (leading to a query-of-death scenario) or may be used to bypass Envoy's access control mechanisms such as path based routing. An attacker can also modify requests from other users that happen to be proximal temporally and spatially.",
"evidence": "osv:CVE-2019-18801",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2019-18801",
"aliases": [
"CVE-2019-18801",
"GHSA-gxvv-x4p2-rppp"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/envoyproxy/envoy",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"last_affected": "44f8c365a1f1798f0af776f6aa64279dc68f5666"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "1.12.1"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v1.12.1",
"v1.12.0",
"v1.11.0",
"v1.10.0",
"v1.9.0",
"v1.8.0",
"v1.7.0",
"v1.6.0",
"v1.5.0",
"v1.4.0",
"v1.3.0",
"v1.2.0",
"v1.1.0",
"v1.0.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2019-18801.json"
}
}
],
"modified": "2026-10-20T10:50:50.563732623Z",
"provider": "osv",
"references": [
"https://groups.google.com/forum/#%21forum/envoy-users",
"https://access.redhat.com/errata/RHSA-2019:4222",
"https://github.com/envoyproxy/envoy/commits/master",
"https://blog.envoyproxy.io",
"https://github.com/envoyproxy/envoy/security/advisories/GHSA-gxvv-x4p2-rppp"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2019-18801",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 382228,
"published_at": "2019-12-13T13:15:11.303+00:00"
}