Description
Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to 1.22.0, _unpack_2bit() and _unpack_4bit() resize unpacked arrays according to attacker-controlled TensorProto.dims without verifying that raw_data or int32_data encodes the declared number of elements. Materializing an untrusted UINT2, INT2, UINT4, INT4, or FLOAT4E2M1 tensor through onnx.numpy_helper.to_array() or onnx.reference.ReferenceEvaluator can therefore expand a small packed payload into a disproportionately large allocation and exhaust memory. This issue is fixed in version 1.22.0.
Published: 2026-10-26
Score: 6.2 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

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Tracking

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History

Mon, 26 Oct 2026 19:15:00 +0000

Type Values Removed Values Added
First Time appeared Onnx
Onnx onnx
Vendors & Products Onnx
Onnx onnx

Mon, 26 Oct 2026 17:45:00 +0000

Type Values Removed Values Added
Description Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to 1.22.0, _unpack_2bit() and _unpack_4bit() resize unpacked arrays according to attacker-controlled TensorProto.dims without verifying that raw_data or int32_data encodes the declared number of elements. Materializing an untrusted UINT2, INT2, UINT4, INT4, or FLOAT4E2M1 tensor through onnx.numpy_helper.to_array() or onnx.reference.ReferenceEvaluator can therefore expand a small packed payload into a disproportionately large allocation and exhaust memory. This issue is fixed in version 1.22.0.
Title ONNX: Denial of service via unchecked expansion of packed sub-byte tensors in ONNX Python APIs
Weaknesses CWE-789
References
Metrics cvssV3_1

{'score': 6.2, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-10-26T17:31:03.716Z

Reserved: 2026-10-23T20:21:45.107Z

Link: CVE-2026-115922

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-26T18:17:40.163

Modified: 2026-10-26T18:34:17.050

Link: CVE-2026-115922

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-26T19:00:08Z

Weaknesses
  • CWE-789

    Memory Allocation with Excessive Size Value