Vulnerability · Published Apr 1, 2026 · Assigned by GitHub_M
CVE-2026-34445ONNX: Malicious ONNX models can crash servers by exploiting unprotected object settings.
High 8.6
In plain English
A high-severity improper input validation in onnx from onnx. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | onnx | no fix listed | DEBIAN-CVE-2026-34445 |
| Debian:13 | onnx | no fix listed | DEBIAN-CVE-2026-34445 |
| Debian:14 | onnx | no fix listed | DEBIAN-CVE-2026-34445 |
| PyPI | onnx | 1.21.0 | GHSA-538c-55jv-c5g9 |
| PyPI | onnx | 1.21.0 | PYSEC-2026-2240 |
| Ubuntu:22.04:LTS | onnx | no fix listed | UBUNTU-CVE-2026-34445 |
| Ubuntu:25.10 | onnx | no fix listed | UBUNTU-CVE-2026-34445 |
| Ubuntu:26.04:LTS | onnx | no fix listed | UBUNTU-CVE-2026-34445 |
| Ubuntu:26.10 | onnx | no fix listed | UBUNTU-CVE-2026-34445 |
Affected products (as reported)
Weakness: CWE-20, CWE-400, CWE-915 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
References
- https://github.com/onnx/onnx/security/advisories/GHSA-538c-55jv-c5g9 x_refsource_CONFIRM
- https://github.com/onnx/onnx/pull/7751 x_refsource_MISC
- https://github.com/onnx/onnx/commit/e30c6935d67cc3eca2fa284e37248e7c0036c46b x_refsource_MISC