Low
node-undici — security advisory
Impact: Undici's HTTP/1.1 client is vulnerable to response queue poisoning on reused keep-alive sockets. An attacker-controlled upstream server can inject an unsolicited HTTP/1.1 response onto an idle socket after a request completes. When the client dispatches the next request on that socket, it associates the injected response with the new request, causing responses to be delivered to the wrong requests. This requires an attacker-controlled or compromised upstream HTTP/1.1 server and keep-alive connection reuse. Patches: Upgrade to undici v6.26.0, v7.28.0 or v8.5.0. Workarounds: Disable keep-alive connection reuse by setting keepAliveTimeout: 0 on the Client or Pool.
- Products
- node-undici
- Affected versions
- 5.22.1+dfsg1+~cs20.10.10.2-1ubuntu1, 5.26.3+dfsg1+~cs23.10.12-2, 7.16.0+dfsg+~cs3.2.0-2, 7.18.2+dfsg+~cs3.2.0-1, 7.18.2+dfsg+~cs3.2.0-1build1, 7.24.6+dfsg+~cs3.2.0-3, 7.3.0+dfsg1+~cs24.12.11-1, 7.3.0+dfsg1+~cs24.12.11-2, 8.5.0+dfsg+~cs3.2.0-2, 8.5.0+dfsg+~cs3.2.0-3, 8.9.0+dfsg+~cs3.2.0-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-6733
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:13 UTC · Revision 1
Source evidence
Impact: Undici's HTTP/1.1 client is vulnerable to response queue poisoning on reused keep-alive sockets. An attacker-controlled upstream server can inject an unsolicited HTTP/1.1 response onto an idle socket after a request completes. When the client dispatches the next request on that socket, it associates the injected response with the new request, causing responses to be delivered to the wrong requests. This requires an attacker-controlled or compromised upstream HTTP/1.1 server and keep-alive connection reuse. Patches: Upgrade to undici v6.26.0, v7.28.0 or v8.5.0. Workarounds: Disable keep-alive connection reuse by setting keepAliveTimeout: 0 on the Client or Pool.
osv:UBUNTU-CVE-2026-6733
node-undici
Fixed versions: Not specified
node-undici
Fixed versions: Not specified
node-undici
Fixed versions: Not specified
node-undici
Fixed versions: Not specified
Complete source record
{
"id": "0f1f35784b1e9dbaea2255352de7d5b134f64a27159941c8781db619ff1222b3",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-6733",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-6733",
"summary": "Impact: Undici's HTTP/1.1 client is vulnerable to response queue poisoning on reused keep-alive sockets. An attacker-controlled upstream server can inject an unsolicited HTTP/1.1 response onto an idle socket after a request completes. When the client dispatches the next request on that socket, it associates the injected response with the new request, causing responses to be delivered to the wrong requests. This requires an attacker-controlled or compromised upstream HTTP/1.1 server and keep-alive connection reuse. Patches: Upgrade to undici v6.26.0, v7.28.0 or v8.5.0. Workarounds: Disable keep-alive connection reuse by setting keepAliveTimeout: 0 on the Client or Pool.",
"evidence": "osv:UBUNTU-CVE-2026-6733",
"products": [
{
"name": {
"value": "node-undici",
"evidence": "/affected/0/package/name"
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"value": "5.22.1+dfsg1+~cs20.10.10.2-1ubuntu1",
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{
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{
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{
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{
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{
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"evidence": "/affected/2/versions"
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{
"value": "8.5.0+dfsg+~cs3.2.0-2",
"evidence": "/affected/2/versions"
},
{
"value": "8.5.0+dfsg+~cs3.2.0-3",
"evidence": "/affected/2/versions"
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{
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{
"name": {
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"affected_versions": [
{
"value": "7.3.0+dfsg1+~cs24.12.11-2",
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{
"value": "7.16.0+dfsg+~cs3.2.0-2",
"evidence": "/affected/3/versions"
},
{
"value": "7.18.2+dfsg+~cs3.2.0-1",
"evidence": "/affected/3/versions"
},
{
"value": "7.18.2+dfsg+~cs3.2.0-1build1",
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],
"severity": "low",
"structured": {
"id": "UBUNTU-CVE-2026-6733",
"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "node-undici",
"purl": "pkg:deb/ubuntu/node-undici?arch=source&distro=noble",
"ecosystem": "Ubuntu:24.04:LTS"
},
"versions": [
"5.22.1+dfsg1+~cs20.10.10.2-1ubuntu1",
"5.26.3+dfsg1+~cs23.10.12-2"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6733.json"
},
"ecosystem_specific": {
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{
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{
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"ecosystem": "Ubuntu:25.10"
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"versions": [
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"database_specific": {
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},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libllhttp9.2",
"binary_version": "9.2.1~7.3.0+dfsg1+~cs24.12.11-2"
},
{
"binary_name": "node-llhttp",
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{
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},
{
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"package": {
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"purl": "pkg:deb/ubuntu/node-undici?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"7.18.2+dfsg+~cs3.2.0-1build1",
"7.24.6+dfsg+~cs3.2.0-3",
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"8.9.0+dfsg+~cs3.2.0-1"
],
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"ecosystem_specific": {
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{
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"package": {
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"purl": "pkg:deb/ubuntu/node-undici?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
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"7.16.0+dfsg+~cs3.2.0-2",
"7.18.2+dfsg+~cs3.2.0-1",
"7.18.2+dfsg+~cs3.2.0-1build1"
],
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{
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}
]
}
}
],
"modified": "2026-10-17T13:00:36.299396251Z",
"provider": "osv",
"upstream": [
"CVE-2026-6733"
],
"references": [
"https://ubuntu.com/security/CVE-2026-6733",
"https://www.cve.org/CVERecord?id=CVE-2026-6733",
"https://github.com/nodejs/undici/security/advisories/GHSA-35p6-xmwp-9g52"
]
},
"related_cves": [
{
"value": "CVE-2026-6733",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 360730,
"published_at": "2026-06-17T18:18:00+00:00"
}