Vulnerability in Onnx
CVE-2026-115922
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 · last modified .
CVSS v3 metric
CVSS v3 base score 6.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Onnx — versions < 1.22.0
Weakness classification (CWE)
References
- github.com/onnx/onnx/security/advisories/GHSA-q69g-f4f5-v8m7
- github.com/onnx/onnx/pull/8033
- github.com/onnx/onnx/pull/8038
- github.com/onnx/onnx/pull/8066
- github.com/onnx/onnx/commit/05c1bc3bceceb8d3cf11e9e7fc7f19f971c44988
- github.com/onnx/onnx/commit/8de2cf6aa47928e6515ac6d9e1a8b4758886a7df
- github.com/onnx/onnx/commit/dce5876d6cc6cc30157af7d26a752ef44976da8e
- github.com/onnx/onnx/releases/tag/v1.22.0
Frequently asked questions
- What is CVE-2026-115922?
- CVE-2026-115922 is a medium-severity vulnerability in Onnx, classified under CWE-789. CVSS score: 6.2/10. Published 2026-10-26.
- How severe is CVE-2026-115922?
- Medium severity. CVSS v3 base score is 6.2 out of 10.