undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields
undici's setCookie function does not fully sanitize cookie attributes. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, a domain value is not checked for semicolons and entries in the unparsed array are not sanitized, so attacker-influenced input can inject additional cookie attributes. For example, a domain value containing a semicolon can append attributes such as SameSite, and an unparsed entry can inject attributes such as HttpOnly, without the caller setting them. Applications that pass user-controlled input to these fields, such as multi-tenant or reverse-proxy servers that scope session cookies to a tenant-supplied domain, can have SameSite CSRF protections bypassed, or the Secure, HttpOnly, and SameSite attributes forced, stripped, or overridden. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-16729
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 7 Nov 2026, 01:12 UTC · Revision 1
Source evidence
undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields
core-osv · Original sourcePublished 29 Jul 2026, 16:45 UTC
undici's setCookie function does not fully sanitize cookie attributes. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, a domain value is not checked for semicolons and entries in the unparsed array are not sanitized, so attacker-influenced input can inject additional cookie attributes. For example, a domain value containing a semicolon can append attributes such as SameSite, and an unparsed entry can inject attributes such as HttpOnly, without the caller setting them. Applications that pass user-controlled input to these fields, such as multi-tenant or reverse-proxy servers that scope session cookies to a tenant-supplied domain, can have SameSite CSRF protections bypassed, or the Secure, HttpOnly, and SameSite attributes forced, stripped, or overridden. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.
osv:CVE-2026-16729
Complete source record
{
"id": "95dd6192581a633552e6d6dd304767194574d0690ac573804769e5c6928e0f84",
"url": "https://osv.dev/vulnerability/CVE-2026-16729",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields",
"summary": "undici's setCookie function does not fully sanitize cookie attributes. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, a domain value is not checked for semicolons and entries in the unparsed array are not sanitized, so attacker-influenced input can inject additional cookie attributes. For example, a domain value containing a semicolon can append attributes such as SameSite, and an unparsed entry can inject attributes such as HttpOnly, without the caller setting them. Applications that pass user-controlled input to these fields, such as multi-tenant or reverse-proxy servers that scope session cookies to a tenant-supplied domain, can have SameSite CSRF protections bypassed, or the Secure, HttpOnly, and SameSite attributes forced, stripped, or overridden. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.",
"evidence": "osv:CVE-2026-16729",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-16729",
"aliases": [
"CVE-2026-16729",
"GHSA-v3r7-h72x-cjcm"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/nodejs/undici",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "01a912e49a50c48009ed2639d2a457a6ec26752a"
},
{
"introduced": "1cfe0949053aac6267f11b919cee9315a27f1fd6"
},
{
"fixed": "9e38fc121d2eb26086d41c7d9379b47a6fada1c5"
},
{
"introduced": "d7fbba51772deecb830a297647456a5e9f9fec57"
},
{
"fixed": "21a8e1ed1843e74c3004a2926c12bb0ceaca6b71"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "6.28.0"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "7.0.0"
},
{
"fixed": "7.29.0"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "8.0.0"
},
{
"fixed": "8.9.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v6.27.0",
"v7.28.0",
"v8.8.0",
"v8.7.0",
"v8.6.0",
"v8.5.0",
"v6.26.0",
"v7.27.2",
"v8.4.1",
"v8.4.0",
"v7.27.1",
"v7.27.0",
"v7.26.0",
"v6.25.0",
"v8.3.0",
"v8.2.0",
"v7.25.0",
"v7.24.8",
"v8.1.0",
"v8.0.3",
"v8.0.2",
"v8.0.1",
"v8.0.0",
"v7.24.7",
"v7.24.6",
"v7.24.5",
"v7.24.4",
"v7.24.3",
"v7.24.2",
"v6.24.1",
"v6.24.0",
"v7.24.1",
"v7.24.0",
"v6.23.0",
"v7.23.0",
"v7.22.0",
"v7.21.0",
"v7.20.0",
"v7.19.2",
"v7.19.1",
"v7.19.0",
"v7.18.2",
"v7.18.1",
"v7.18.0",
"v6.22.0",
"v7.17.0",
"v7.16.0",
"v7.15.0",
"v6.21.3",
"v7.14.0",
"v7.13.0",
"v7.12.0",
"v7.11.0",
"v7.10.0",
"v6.21.2",
"v7.9.0",
"v7.8.0",
"v7.7.0",
"v7.5.0",
"v7.6.0",
"v7.4.0",
"v6.21.1",
"v7.3.0",
"v7.2.3",
"v7.2.2",
"v7.2.1",
"v7.2.0",
"v7.1.1",
"v7.1.0",
"v7.0.0",
"v6.21.0",
"v6.20.1",
"v6.20.0",
"v6.19.8",
"v6.19.7",
"v6.19.6",
"v6.19.5",
"v6.19.4",
"v6.19.3",
"v6.19.2",
"v6.19.1",
"v6.19.0",
"v6.18.2",
"v6.18.1",
"v6.18.0",
"v6.17.0",
"v6.16.1",
"v6.16.0",
"v6.15.0",
"v6.14.1",
"v6.14.0",
"v6.13.0",
"v6.12.0",
"v6.11.1",
"v6.11.0",
"v6.10.2",
"v6.10.1",
"v6.10.0",
"v6.9.0",
"v6.8.0",
"v6.7.1",
"v6.7.0",
"v6.6.2",
"v6.6.1",
"v5.28.2",
"v6.6.0",
"v6.5.0",
"v6.4.0",
"v6.3.0",
"v6.2.1",
"v6.2.0",
"v6.1.0",
"v6.0.1",
"v6.0.0",
"v5.28.1",
"v5.28.0",
"v5.27.2",
"v5.27.1",
"v5.27.0",
"v5.26.5",
"v5.26.4",
"v5.26.3",
"v5.26.2",
"v5.26.1",
"v5.26.0",
"v5.23.4",
"v5.25.3",
"v5.25.2",
"v5.25.1",
"v5.25.0",
"v5.24.0",
"v5.23.0",
"v5.22.1",
"v5.22.0",
"v5.21.2",
"v5.21.1",
"v5.21.0",
"v5.20.0",
"v5.19.1",
"v5.19.0",
"v5.18.0",
"v5.17.1",
"v5.17.0",
"v5.16.0",
"v5.15.2",
"v5.15.1",
"v5.15.0",
"v5.14.0",
"v5.13.0",
"v5.12.0",
"v5.11.0",
"v5.10.0",
"v5.9.1",
"v5.8.2",
"v5.8.1",
"v5.8.0",
"v5.7.0",
"v5.6.1",
"v5.6.0",
"v5.5.1",
"v5.5.0",
"v5.4.0",
"v5.3.0",
"v5.2.0",
"v5.1.1",
"v5.1.0",
"v5.0.0",
"v4.16.0",
"v4.15.1",
"v4.15.0",
"v4.14.1",
"v4.14.0",
"v4.13.0",
"v4.12.2",
"v4.12.0",
"v4.11.3",
"v4.11.2",
"v4.11.1",
"v4.11.0",
"v4.10.4",
"v4.10.3",
"v4.10.2",
"v4.10.1",
"v4.10.0",
"v4.9.5",
"v4.9.4",
"v4.9.3",
"v4.9.2",
"v4.9.1",
"v4.9.0",
"v4.8.2",
"v4.8.1",
"v4.8.0",
"v4.7.3",
"v4.7.2",
"v4.7.1",
"v4.7.0",
"v4.6.0",
"v4.5.1",
"v4.5.0",
"v4.4.7",
"v4.4.6",
"v4.4.5",
"v4.4.4",
"v4.4.3",
"v4.4.2",
"v4.4.1",
"v4.3.1",
"v4.3.0",
"v4.2.2",
"v4.2.1",
"v4.1.1",
"v4.1.0",
"v4.0.0",
"v4.0.0-rc.8",
"v4.0.0-rc.7",
"v4.0.0-rc.5",
"v4.0.0-rc.4",
"v4.0.0-rc.3",
"v4.0.0-rc.2",
"v4.0.0-rc.1",
"v4.0.0-alpha.5",
"v4.0.0-alpha.4",
"v4.0.0-alpha.2",
"v4.0.0-alpha.1",
"v4.0.0-alpha.0",
"v3.3.1",
"v3.3.0",
"v3.2.0",
"v3.1.0",
"v3.0.0",
"v2.1.0",
"v2.0.7",
"v2.0.6",
"v2.0.5",
"v2.0.4",
"v2.0.3",
"v2.0.2",
"v2.0.1",
"v2.0.0",
"v1.3.1",
"v1.3.0",
"v1.2.6",
"v1.2.5",
"v1.2.2",
"v1.2.1",
"v1.2.0",
"v1.1.0",
"v1.0.3",
"v1.0.2",
"v1.0.1",
"v1.0.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-16729.json"
}
}
],
"modified": "2026-10-28T02:30:48.864045123Z",
"provider": "osv",
"references": [
"https://cna.openjsf.org/security-advisories.html",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16729.json",
"https://github.com/nodejs/undici/security/advisories/GHSA-v3r7-h72x-cjcm",
"https://nvd.nist.gov/vuln/detail/CVE-2026-16729"
],
"provider_metadata": {
"cwe_ids": [
"CWE-74"
],
"cna_assigner": "openjs",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16729.json"
}
},
"related_cves": [
{
"value": "CVE-2026-16729",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 516882,
"published_at": "2026-07-29T16:45:57.001+00:00"
}