Medium
onnx — security advisory
In ONNX before 1.21.0, the 'save_external_data' function builds the external-data file path from the model's external_data location field and opens it for writing without 'O_NOFOLLOW/O_EXCL', after a non-atomic 'os.path.isfile()' check. A local attacker with write access to the directory where a victim serializes external data can deterministically pre-plant a symlink that is being followed, causing the victim's write to append to any file the victim can write, e.g. ~/.ssh/authorized_keys, cron files, or application configs. Fixed in 1.21.0.
- Products
- onnx
- Affected versions
- 1.12.0-2, 1.13.1-1, 1.13.1-2, 1.13.1-3, 1.14.1-1, 1.14.1-2, 1.14.1-2.1, 1.14.1-2.1~exp1, 1.16.1-1, 1.16.2-1, 1.17.0-1, 1.17.0-2, 1.17.0-3, 1.19.1-1~exp1, 1.20.0-1, 1.20.0-1~exp1, 1.20.0-3, 1.20.0-4, 1.20.0-5, 1.20.0-6, 1.21.0-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-49114
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 20:00 UTC · Revision 1
Source evidence
In ONNX before 1.21.0, the 'save_external_data' function builds the external-data file path from the model's external_data location field and opens it for writing without 'O_NOFOLLOW/O_EXCL', after a non-atomic 'os.path.isfile()' check. A local attacker with write access to the directory where a victim serializes external data can deterministically pre-plant a symlink that is being followed, causing the victim's write to append to any file the victim can write, e.g. ~/.ssh/authorized_keys, cron files, or application configs. Fixed in 1.21.0.
osv:DEBIAN-CVE-2026-49114
onnx
Fixed versions: Not specified
onnx
Fixed versions: Not specified
onnx
Fixed versions: Not specified
Complete source record
{
"id": "7069e23b94c58da7beb6ddf40218dfe9f9306476804a125d71383f5d2e74ef4d",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-49114",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-49114",
"summary": "In ONNX before 1.21.0, the 'save_external_data' function builds the external-data file path from the model's external_data location field and opens it for writing without 'O_NOFOLLOW/O_EXCL', after a non-atomic 'os.path.isfile()' check. A local attacker with write access to the directory where a victim serializes external data can deterministically pre-plant a symlink that is being followed, causing the victim's write to append to any file the victim can write, e.g. ~/.ssh/authorized_keys, cron files, or application configs. Fixed in 1.21.0.",
"evidence": "osv:DEBIAN-CVE-2026-49114",
"products": [
{
"name": {
"value": "onnx",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.12.0-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.13.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.13.1-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.13.1-3",
"evidence": "/affected/0/versions"
},
{
"value": "1.14.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.14.1-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.14.1-2.1",
"evidence": "/affected/0/versions"
},
{
"value": "1.14.1-2.1~exp1",
"evidence": "/affected/0/versions"
},
{
"value": "1.16.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.16.2-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.17.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.17.0-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.17.0-3",
"evidence": "/affected/0/versions"
},
{
"value": "1.19.1-1~exp1",
"evidence": "/affected/0/versions"
},
{
"value": "1.20.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.20.0-1~exp1",
"evidence": "/affected/0/versions"
},
{
"value": "1.20.0-3",
"evidence": "/affected/0/versions"
},
{
"value": "1.20.0-4",
"evidence": "/affected/0/versions"
},
{
"value": "1.20.0-5",
"evidence": "/affected/0/versions"
},
{
"value": "1.20.0-6",
"evidence": "/affected/0/versions"
},
{
"value": "1.21.0-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "onnx",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.17.0-3",
"evidence": "/affected/1/versions"
},
{
"value": "1.19.1-1~exp1",
"evidence": "/affected/1/versions"
},
{
"value": "1.20.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "1.20.0-1~exp1",
"evidence": "/affected/1/versions"
},
{
"value": "1.20.0-3",
"evidence": "/affected/1/versions"
},
{
"value": "1.20.0-4",
"evidence": "/affected/1/versions"
},
{
"value": "1.20.0-5",
"evidence": "/affected/1/versions"
},
{
"value": "1.20.0-6",
"evidence": "/affected/1/versions"
},
{
"value": "1.21.0-1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "onnx",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.17.0-3",
"evidence": "/affected/2/versions"
},
{
"value": "1.19.1-1~exp1",
"evidence": "/affected/2/versions"
},
{
"value": "1.20.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.20.0-1~exp1",
"evidence": "/affected/2/versions"
},
{
"value": "1.20.0-3",
"evidence": "/affected/2/versions"
},
{
"value": "1.20.0-4",
"evidence": "/affected/2/versions"
},
{
"value": "1.20.0-5",
"evidence": "/affected/2/versions"
},
{
"value": "1.20.0-6",
"evidence": "/affected/2/versions"
},
{
"value": "1.21.0-1",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2026-49114",
"aliases": [
"DEBIAN-CVE-2026-49114"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "onnx",
"purl": "pkg:deb/debian/onnx?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"1.12.0-2",
"1.13.1-1",
"1.13.1-2",
"1.13.1-3",
"1.14.1-1",
"1.14.1-2",
"1.14.1-2.1",
"1.14.1-2.1~exp1",
"1.16.1-1",
"1.16.2-1",
"1.17.0-1",
"1.17.0-2",
"1.17.0-3",
"1.19.1-1~exp1",
"1.20.0-1",
"1.20.0-1~exp1",
"1.20.0-3",
"1.20.0-4",
"1.20.0-5",
"1.20.0-6",
"1.21.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49114.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "onnx",
"purl": "pkg:deb/debian/onnx?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1.17.0-3",
"1.19.1-1~exp1",
"1.20.0-1",
"1.20.0-1~exp1",
"1.20.0-3",
"1.20.0-4",
"1.20.0-5",
"1.20.0-6",
"1.21.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49114.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "onnx",
"purl": "pkg:deb/debian/onnx?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1.17.0-3",
"1.19.1-1~exp1",
"1.20.0-1",
"1.20.0-1~exp1",
"1.20.0-3",
"1.20.0-4",
"1.20.0-5",
"1.20.0-6",
"1.21.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49114.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-16T09:47:35.300075949Z",
"provider": "osv",
"upstream": [
"CVE-2026-49114"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-49114"
]
},
"related_cves": [
{
"value": "CVE-2026-49114",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 338656,
"published_at": "2026-08-21T16:17:17.863+00:00"
}