CVE-2026-34445CWE-20CWE-400CWE-915

ONNX: Malicious ONNX models can crash servers by exploiting unprotected object settings.

High · published April 1, 2026

CVSS v3.1
8.6
EPSS
1%
Percentile
42.3
In the wild
Unconfirmed
What it is

Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to version 1.21.0, the ExternalDataInfo class in ONNX was using Python’s setattr() function to load metadata (like file paths or data lengths) directly from an ONNX model file. It didn’t check if the "keys" in the file were valid. Due to this, an attacker could craft a malicious model that overwrites internal object properties. This issue has been patched in version 1.21.0.

The record
Technical detail
CVSS v3.1
8.6 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
CVSS v4.0
Not supplied
EPSS
0.00506 · 42.3th percentile
Weaknesses
CWE-20 · Improper Input Validation; CWE-400 · Uncontrolled Resource Consumption; CWE-915 · Improperly Controlled Modification of Dynamically-Determined Object Attributes
Published
2026-04-01T17:30Z
EPSS history
Timeline
  • 01 APR 17:30Z
    ONNX: Malicious ONNX models can crash servers by exploiting unprotected object settings.
    cvelistv5