Microsoft Security Response Center guidance
Vendor revision: Nov 3, 2026Release Notes
Vulnerability intelligence
CVE-2026-115920 and is rated Medium severity with a CVSS score of 6.2. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Release Notes
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.
Source: NVD