High
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
- 1.13.1-3, 1.13.1-3build1, 1.14.1-2, 1.14.1-2.1, 1.14.1-2.1build1, 1.14.1-2.1build2, 1.14.1-2.1ubuntu0.1~esm1, 1.17.0-3build1, 1.20.0-1, 1.20.0-6, 1.7.0+dfsg-3build1, 1.7.0+dfsg-3build2, 1.7.0+dfsg-3ubuntu1, 1.7.0+dfsg-3ubuntu2
- Fixed versions
- Not specified
- CVEs
- CVE-2026-49114
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:07 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:UBUNTU-CVE-2026-49114
onnx
Fixed versions: Not specified
onnx
Fixed versions: Not specified
onnx
Fixed versions: Not specified
onnx
Fixed versions: Not specified
Complete source record
{
"id": "3cdce8caf1ca2330fd6724a986100abb1005c6cf1eb28bdf923de8d35ecd12d6",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-49114",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-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:UBUNTU-CVE-2026-49114",
"products": [
{
"name": {
"value": "onnx",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.7.0+dfsg-3build1",
"evidence": "/affected/0/versions"
},
{
"value": "1.7.0+dfsg-3build2",
"evidence": "/affected/0/versions"
},
{
"value": "1.7.0+dfsg-3ubuntu1",
"evidence": "/affected/0/versions"
},
{
"value": "1.7.0+dfsg-3ubuntu2",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "onnx",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.13.1-3",
"evidence": "/affected/1/versions"
},
{
"value": "1.13.1-3build1",
"evidence": "/affected/1/versions"
},
{
"value": "1.14.1-2",
"evidence": "/affected/1/versions"
},
{
"value": "1.14.1-2.1",
"evidence": "/affected/1/versions"
},
{
"value": "1.14.1-2.1build1",
"evidence": "/affected/1/versions"
},
{
"value": "1.14.1-2.1build2",
"evidence": "/affected/1/versions"
},
{
"value": "1.14.1-2.1ubuntu0.1~esm1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "onnx",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.20.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.20.0-6",
"evidence": "/affected/2/versions"
}
]
},
{
"name": {
"value": "onnx",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.17.0-3build1",
"evidence": "/affected/3/versions"
},
{
"value": "1.20.0-1",
"evidence": "/affected/3/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "UBUNTU-CVE-2026-49114",
"aliases": [
"UBUNTU-CVE-2026-49114"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H"
},
{
"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"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "onnx",
"purl": "pkg:deb/ubuntu/onnx?arch=source&distro=jammy",
"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
"1.7.0+dfsg-3build1",
"1.7.0+dfsg-3build2",
"1.7.0+dfsg-3ubuntu1",
"1.7.0+dfsg-3ubuntu2"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-49114.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libonnx-testdata",
"binary_version": "1.7.0+dfsg-3ubuntu2"
},
{
"binary_name": "libonnx1",
"binary_version": "1.7.0+dfsg-3ubuntu2"
},
{
"binary_name": "libonnxifi",
"binary_version": "1.7.0+dfsg-3ubuntu2"
},
{
"binary_name": "python3-onnx",
"binary_version": "1.7.0+dfsg-3ubuntu2"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "onnx",
"purl": "pkg:deb/ubuntu/onnx?arch=source&distro=esm-apps%2Fnoble",
"ecosystem": "Ubuntu:Pro:24.04:LTS"
},
"versions": [
"1.13.1-3",
"1.13.1-3build1",
"1.14.1-2",
"1.14.1-2.1",
"1.14.1-2.1build1",
"1.14.1-2.1build2",
"1.14.1-2.1ubuntu0.1~esm1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-49114.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libonnx-testdata",
"binary_version": "1.14.1-2.1ubuntu0.1~esm1"
},
{
"binary_name": "libonnx1t64",
"binary_version": "1.14.1-2.1ubuntu0.1~esm1"
},
{
"binary_name": "python3-onnx",
"binary_version": "1.14.1-2.1ubuntu0.1~esm1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "onnx",
"purl": "pkg:deb/ubuntu/onnx?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"1.20.0-1",
"1.20.0-6"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-49114.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libonnx-testdata",
"binary_version": "1.20.0-6"
},
{
"binary_name": "libonnx1l",
"binary_version": "1.20.0-6"
},
{
"binary_name": "python3-onnx",
"binary_version": "1.20.0-6"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "onnx",
"purl": "pkg:deb/ubuntu/onnx?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
"1.17.0-3build1",
"1.20.0-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-49114.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libonnx-testdata",
"binary_version": "1.20.0-1"
},
{
"binary_name": "libonnx1t64",
"binary_version": "1.20.0-1"
},
{
"binary_name": "python3-onnx",
"binary_version": "1.20.0-1"
}
]
}
}
],
"modified": "2026-10-17T13:00:24.148911624Z",
"provider": "osv",
"upstream": [
"CVE-2026-49114"
],
"references": [
"https://ubuntu.com/security/CVE-2026-49114",
"https://www.cve.org/CVERecord?id=CVE-2026-49114",
"https://github.com/onnx/onnx/security/advisories/GHSA-q56x-g2fj-4rj6"
]
},
"related_cves": [
{
"value": "CVE-2026-49114",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 360497,
"published_at": "2026-08-21T16:17:00+00:00"
}