---
id: CVE-2026-115921
title: >-
  ONNX: Null Pointer Dereference in ScanInferenceFunction Due to Missing
  Required Attribute
summary: >-
  Open Neural Network Exchange (ONNX) is an open standard for machine learning
  interoperability. From 1.4.0 until 1.22.0, ScanInferenceFunction,
  ScanInferenceFunction_opset8, and ScanInferenceFunction_opset9 do not safely
  validate the requ…
severity: medium
cvss: 6.2
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-195
  - CWE-476
vendor: onnx
product: onnx
affected:
  - 'onnx >= 1.4.0, < 1.22.0'
published: '2026-10-26'
updated: '2026-10-26'
sourceUpdated: '2026-10-26T17:28:41.420Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-115921'
references:
  - url: 'https://github.com/onnx/onnx/security/advisories/GHSA-m4pr-6v3c-6fgr'
    label: 'https://github.com/onnx/onnx/security/advisories/GHSA-m4pr-6v3c-6fgr'
  - url: 'https://github.com/onnx/onnx/pull/7916'
    label: 'https://github.com/onnx/onnx/pull/7916'
  - url: >-
      https://github.com/onnx/onnx/commit/dd6bc92ea39fd2274fd671f0734b0b8b558356f5
    label: >-
      https://github.com/onnx/onnx/commit/dd6bc92ea39fd2274fd671f0734b0b8b558356f5
  - url: 'https://github.com/onnx/onnx/releases/tag/v1.22.0'
    label: 'https://github.com/onnx/onnx/releases/tag/v1.22.0'
tags:
  - cve.org
ingestedAt: '2026-10-26T17:33:33.052Z'
---

## Overview

Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. From 1.4.0 until 1.22.0, ScanInferenceFunction, ScanInferenceFunction_opset8, and ScanInferenceFunction_opset9 do not safely validate the required num_scan_inputs attribute. A missing attribute is dereferenced as a null pointer, while a negative value is converted to size_t and can reach an exceptional oversized allocation path. An untrusted model can therefore terminate or disrupt shape inference, including a negative-value model that can pass onnx.checker.check_model(). This issue is fixed in version 1.22.0.

## Affected

- `onnx >= 1.4.0, < 1.22.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.