High
busybox — security advisory
A flaw was found in BusyBox httpd's reverse proxy feature. When the proxy is configured to forward requests matching a URL prefix to a backend server, only the first HTTP request on a TCP connection has its path rewritten. An attacker can send a pipelined second request that is relayed verbatim to the backend, bypassing the configured path restrictions. This allows accessing arbitrary paths on the backend server that were not intended to be exposed through the proxy.
- Products
- busybox
- Affected versions
- 1:1.35.0-4, 1:1.35.0-4+deb12u1, 1:1.36.0-1~exp1, 1:1.36.1-1, 1:1.36.1-2, 1:1.36.1-3, 1:1.36.1-3.1, 1:1.36.1-4, 1:1.36.1-5, 1:1.36.1-6, 1:1.36.1-6~exp.1, 1:1.36.1-7, 1:1.36.1-8, 1:1.36.1-9, 1:1.37.0-1, 1:1.37.0-10, 1:1.37.0-10.1, 1:1.37.0-2, 1:1.37.0-3, 1:1.37.0-4, 1:1.37.0-5, 1:1.37.0-6, 1:1.37.0-7, 1:1.37.0-8, 1:1.37.0-9, 1:1.38.0-1, 1:1.38.0-2, 1:1.38.0-3
- Fixed versions
- Not specified
- CVEs
- CVE-2026-88829
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 19:59 UTC · Revision 1
Source evidence
A flaw was found in BusyBox httpd's reverse proxy feature. When the proxy is configured to forward requests matching a URL prefix to a backend server, only the first HTTP request on a TCP connection has its path rewritten. An attacker can send a pipelined second request that is relayed verbatim to the backend, bypassing the configured path restrictions. This allows accessing arbitrary paths on the backend server that were not intended to be exposed through the proxy.
osv:DEBIAN-CVE-2026-88829
busybox
Fixed versions: Not specified
busybox
Fixed versions: Not specified
busybox
Fixed versions: Not specified
Complete source record
{
"id": "1b35956d653bfdbbb487d9249a035e71881b2db512f3d7f92c63a3f04b7780b9",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-88829",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-88829",
"summary": "A flaw was found in BusyBox httpd's reverse proxy feature. When the proxy is configured to forward requests matching a URL prefix to a backend server, only the first HTTP request on a TCP connection has its path rewritten. An attacker can send a pipelined second request that is relayed verbatim to the backend, bypassing the configured path restrictions. This allows accessing arbitrary paths on the backend server that were not intended to be exposed through the proxy.",
"evidence": "osv:DEBIAN-CVE-2026-88829",
"products": [
{
"name": {
"value": "busybox",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1:1.35.0-4",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.35.0-4+deb12u1",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.0-1~exp1",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-2",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-3",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-3.1",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-4",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-5",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-6",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-6~exp.1",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-7",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-8",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.36.1-9",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-10",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-10.1",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-2",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-3",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-4",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-5",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-6",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-7",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-8",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.37.0-9",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.38.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.38.0-2",
"evidence": "/affected/0/versions"
},
{
"value": "1:1.38.0-3",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "busybox",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1:1.37.0-10",
"evidence": "/affected/1/versions"
},
{
"value": "1:1.37.0-10.1",
"evidence": "/affected/1/versions"
},
{
"value": "1:1.37.0-6",
"evidence": "/affected/1/versions"
},
{
"value": "1:1.37.0-7",
"evidence": "/affected/1/versions"
},
{
"value": "1:1.37.0-8",
"evidence": "/affected/1/versions"
},
{
"value": "1:1.37.0-9",
"evidence": "/affected/1/versions"
},
{
"value": "1:1.38.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "1:1.38.0-2",
"evidence": "/affected/1/versions"
},
{
"value": "1:1.38.0-3",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "busybox",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1:1.37.0-10",
"evidence": "/affected/2/versions"
},
{
"value": "1:1.37.0-10.1",
"evidence": "/affected/2/versions"
},
{
"value": "1:1.37.0-6",
"evidence": "/affected/2/versions"
},
{
"value": "1:1.37.0-7",
"evidence": "/affected/2/versions"
},
{
"value": "1:1.37.0-8",
"evidence": "/affected/2/versions"
},
{
"value": "1:1.37.0-9",
"evidence": "/affected/2/versions"
},
{
"value": "1:1.38.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "1:1.38.0-2",
"evidence": "/affected/2/versions"
},
{
"value": "1:1.38.0-3",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-88829",
"aliases": [
"DEBIAN-CVE-2026-88829"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "busybox",
"purl": "pkg:deb/debian/busybox?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"1:1.35.0-4",
"1:1.35.0-4+deb12u1",
"1:1.36.0-1~exp1",
"1:1.36.1-1",
"1:1.36.1-2",
"1:1.36.1-3",
"1:1.36.1-3.1",
"1:1.36.1-4",
"1:1.36.1-5",
"1:1.36.1-6",
"1:1.36.1-6~exp.1",
"1:1.36.1-7",
"1:1.36.1-8",
"1:1.36.1-9",
"1:1.37.0-1",
"1:1.37.0-10",
"1:1.37.0-10.1",
"1:1.37.0-2",
"1:1.37.0-3",
"1:1.37.0-4",
"1:1.37.0-5",
"1:1.37.0-6",
"1:1.37.0-7",
"1:1.37.0-8",
"1:1.37.0-9",
"1:1.38.0-1",
"1:1.38.0-2",
"1:1.38.0-3"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-88829.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "busybox",
"purl": "pkg:deb/debian/busybox?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1:1.37.0-10",
"1:1.37.0-10.1",
"1:1.37.0-6",
"1:1.37.0-7",
"1:1.37.0-8",
"1:1.37.0-9",
"1:1.38.0-1",
"1:1.38.0-2",
"1:1.38.0-3"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-88829.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "busybox",
"purl": "pkg:deb/debian/busybox?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1:1.37.0-10",
"1:1.37.0-10.1",
"1:1.37.0-6",
"1:1.37.0-7",
"1:1.37.0-8",
"1:1.37.0-9",
"1:1.38.0-1",
"1:1.38.0-2",
"1:1.38.0-3"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-88829.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-16T09:47:32.391641331Z",
"provider": "osv",
"upstream": [
"CVE-2026-88829"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-88829"
]
},
"related_cves": [
{
"value": "CVE-2026-88829",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 338627,
"published_at": "2026-10-14T10:17:57.077+00:00"
}