starlette — security advisory
Starlette is a lightweight ASGI framework/toolkit. Prior to 1.3.0, the HTTP request path is not validated before being used to reconstruct request.url. Because request.url is rebuilt by concatenating {scheme}://{host}{path} and re-parsing the result, a path that does not begin with / (for example @google.com) moves the authority boundary during re-parsing, so request.url.hostname and request.url.netloc become attacker-controlled. Code that reads request.url.hostname (rather than the Host header or scope) can therefore be misled into trusting an attacker-supplied host. This vulnerability is fixed in 1.3.0.
- Products
- starlette
- Affected versions
- 0.26.1-1, 0.26.1-1+deb12u1, 0.46.1-3, 0.46.1-3+deb13u1, 0.46.1-3+deb13u2, 0.50.0-1, 1.0.0-1, 1.1.0-1
- Fixed versions
- 0.26.1-1+deb12u2, 0.46.1-3+deb13u3, 1.3.1-1
- CVEs
- CVE-2026-54282
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 12:17 UTC · Revision 2
Source evidence
Starlette is a lightweight ASGI framework/toolkit. Prior to 1.3.0, the HTTP request path is not validated before being used to reconstruct request.url. Because request.url is rebuilt by concatenating {scheme}://{host}{path} and re-parsing the result, a path that does not begin with / (for example @google.com) moves the authority boundary during re-parsing, so request.url.hostname and request.url.netloc become attacker-controlled. Code that reads request.url.hostname (rather than the Host header or scope) can therefore be misled into trusting an attacker-supplied host. This vulnerability is fixed in 1.3.0.
osv:DEBIAN-CVE-2026-54282
starlette
Fixed versions: 0.26.1-1+deb12u2
starlette
Fixed versions: 0.46.1-3+deb13u3
starlette
Fixed versions: 1.3.1-1
Complete source record
{
"id": "f7b1ef64470334d321341fb4f7a9d90e2709aa0c09ed8687cb71839518f3f298",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-54282",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-54282",
"summary": "Starlette is a lightweight ASGI framework/toolkit. Prior to 1.3.0, the HTTP request path is not validated before being used to reconstruct request.url. Because request.url is rebuilt by concatenating {scheme}://{host}{path} and re-parsing the result, a path that does not begin with / (for example @google.com) moves the authority boundary during re-parsing, so request.url.hostname and request.url.netloc become attacker-controlled. Code that reads request.url.hostname (rather than the Host header or scope) can therefore be misled into trusting an attacker-supplied host. This vulnerability is fixed in 1.3.0.",
"evidence": "osv:DEBIAN-CVE-2026-54282",
"products": [
{
"name": {
"value": "starlette",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "0.26.1-1+deb12u2",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "0.26.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "0.26.1-1+deb12u1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "starlette",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "0.46.1-3+deb13u3",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": [
{
"value": "0.46.1-3",
"evidence": "/affected/1/versions"
},
{
"value": "0.46.1-3+deb13u1",
"evidence": "/affected/1/versions"
},
{
"value": "0.46.1-3+deb13u2",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "starlette",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.3.1-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "0.46.1-3",
"evidence": "/affected/2/versions"
},
{
"value": "0.50.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.0.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.1.0-1",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2026-54282",
"aliases": [
"DEBIAN-CVE-2026-54282"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.26.1-1+deb12u2"
}
]
}
],
"package": {
"name": "starlette",
"purl": "pkg:deb/debian/starlette?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"0.26.1-1",
"0.26.1-1+deb12u1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54282.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.46.1-3+deb13u3"
}
]
}
],
"package": {
"name": "starlette",
"purl": "pkg:deb/debian/starlette?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"0.46.1-3",
"0.46.1-3+deb13u1",
"0.46.1-3+deb13u2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54282.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.3.1-1"
}
]
}
],
"package": {
"name": "starlette",
"purl": "pkg:deb/debian/starlette?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"0.46.1-3",
"0.50.0-1",
"1.0.0-1",
"1.1.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54282.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T11:47:28.716516948Z",
"provider": "osv",
"upstream": [
"CVE-2026-54282"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-54282"
]
},
"related_cves": [
{
"value": "CVE-2026-54282",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 450788,
"published_at": "2026-06-22T18:16:46.807+00:00"
}