ONNX: Malicious ONNX models can crash servers by exploiting unprotected object settings.
Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to version 1.21.0, the ExternalDataInfo class in ONNX was using Python’s setattr() function to load metadata (like file paths or data lengths) directly from an ONNX model file. It didn’t check if the "keys" in the file were valid. Due to this, an attacker could craft a malicious model that overwrites internal object properties. This issue has been patched in version 1.21.0.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-34445
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 7 Nov 2026, 03:38 UTC · Revision 1
Source evidence
ONNX: Malicious ONNX models can crash servers by exploiting unprotected object settings.
core-osv · Original sourcePublished 1 Apr 2026, 17:30 UTC
Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to version 1.21.0, the ExternalDataInfo class in ONNX was using Python’s setattr() function to load metadata (like file paths or data lengths) directly from an ONNX model file. It didn’t check if the "keys" in the file were valid. Due to this, an attacker could craft a malicious model that overwrites internal object properties. This issue has been patched in version 1.21.0.
osv:CVE-2026-34445
Complete source record
{
"id": "0a0bc19509904aac3440450c0cc02518645ea3fbe3b3c3484671d182977ab7db",
"url": "https://osv.dev/vulnerability/CVE-2026-34445",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "ONNX: Malicious ONNX models can crash servers by exploiting unprotected object settings.",
"summary": "Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to version 1.21.0, the ExternalDataInfo class in ONNX was using Python’s setattr() function to load metadata (like file paths or data lengths) directly from an ONNX model file. It didn’t check if the \"keys\" in the file were valid. Due to this, an attacker could craft a malicious model that overwrites internal object properties. This issue has been patched in version 1.21.0.",
"evidence": "osv:CVE-2026-34445",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-34445",
"aliases": [
"CVE-2026-34445",
"GHSA-538c-55jv-c5g9",
"PYSEC-2026-2240"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/onnx/onnx",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "be2b5fde82d9c8874f3d19328bdfe3b6962dc67b"
},
{
"fixed": "e30c6935d67cc3eca2fa284e37248e7c0036c46b"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:linuxfoundation:onnx:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "1.21.0"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "e30c6935d67cc3eca2fa284e37248e7c0036c46b"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"v1.3.0",
"v1.1.0",
"v0.2",
"v0.1"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-34445.json"
}
}
],
"modified": "2026-10-28T02:30:49.616077859Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34445.json",
"https://github.com/onnx/onnx/security/advisories/GHSA-538c-55jv-c5g9",
"https://nvd.nist.gov/vuln/detail/CVE-2026-34445",
"https://github.com/onnx/onnx/commit/e30c6935d67cc3eca2fa284e37248e7c0036c46b",
"https://github.com/onnx/onnx/pull/7751"
],
"provider_metadata": {
"cwe_ids": [
"CWE-20",
"CWE-400",
"CWE-915"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34445.json"
}
},
"related_cves": [
{
"value": "CVE-2026-34445",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 517820,
"published_at": "2026-04-01T17:30:19.994+00:00"
}