ONNX: Out-of-bounds read in ConvTranspose shape inference via undersized weight rank

{
  "id": "6fd68b046db4e5f6389f7883fb50fbbed372e93f430d711cd7e64d7a566ba61a",
  "url": "https://www.cve.org/CVERecord?id=CVE-2026-115920",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "ONNX: Out-of-bounds read in ConvTranspose shape inference via undersized weight rank",
    "summary": "Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. From 1.2.1 until 1.22.0, ConvTranspose shape inference processes a weight tensor with fewer than three dimensions without a kernel_shape attribute by deriving an empty effective_kernel_shape and indexing it for the input's spatial dimensions. The flaw affects convTransposeShapeInference_opset11() and the current inference path, and an untrusted model that can pass onnx.checker.check_model() can crash onnx.shape_inference.infer_shapes(), causing denial of service without demonstrated confidentiality or integrity impact. This issue is fixed in version 1.22.0.",
    "evidence": "cve:CVE-2026-115920",
    "products": [
      {
        "name": {
          "value": "onnx",
          "evidence": "/containers/cna/affected/0/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-115920",
      "aliases": [
        "CVE-2026-115920"
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "scope": "UNCHANGED",
            "version": "3.1",
            "baseScore": 6.2,
            "attackVector": "LOCAL",
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "integrityImpact": "NONE",
            "userInteraction": "NONE",
            "attackComplexity": "LOW",
            "availabilityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "confidentialityImpact": "NONE"
          }
        }
      ],
      "affected": [
        {
          "vendor": "onnx",
          "product": "onnx",
          "versions": [
            {
              "status": "affected",
              "version": ">= 1.2.1, < 1.22.0"
            }
          ]
        }
      ],
      "modified": "2026-10-26T19:48:35.202Z",
      "provider": "cve",
      "references": [
        "https://github.com/onnx/onnx/security/advisories/GHSA-6pwm-x34p-fvj2",
        "https://github.com/onnx/onnx/pull/7997",
        "https://github.com/onnx/onnx/commit/2ec288908952eea9dcf48d4b197915e1f72c6abf",
        "https://github.com/onnx/onnx/releases/tag/v1.22.0"
      ],
      "provider_metadata": {
        "adp": [
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            "title": "CISA ADP Vulnrichment",
            "metrics": [
              {
                "other": {
                  "type": "ssvc",
                  "content": {
                    "id": "CVE-2026-115920",
                    "role": "CISA Coordinator",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "version": "2.0.3",
                    "timestamp": "2026-10-26T19:30:01.679717Z"
                  }
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            "providerMetadata": {
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP",
              "dateUpdated": "2026-10-26T19:48:35.202Z"
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        "cna": {
          "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
          "shortName": "GitHub_M",
          "dateUpdated": "2026-10-26T17:26:40.506Z"
        }
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    "related_cves": [
      {
        "value": "CVE-2026-115920",
        "evidence": "/cveMetadata/cveId"
      }
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    "security_relevant": true,
    "severity_evidence": "/containers/cna/metrics"
  },
  "source_id": "core-cve",
  "document_id": 338314,
  "published_at": "2026-10-26T17:26:40.506+00:00"
}