Skip to content
Heist/ feed
Back to feed
High

ONNX: Malicious ONNX models can crash servers by exploiting unprotected object settings.

Type: advisorySources: OSV

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 source

Published 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"
}