CVE-2026-34446
ONNX: Arbitrary File Read via ExternalData Hardlink Bypass in ONNX load
Description
Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to version 1.21.0, there is an issue in onnx.load, the code checks for symlinks to prevent path traversal, but completely misses hardlinks because a hardlink looks exactly like a regular file on the filesystem. This issue has been patched in version 1.21.0.
INFO
Published Date :
April 1, 2026, 6:16 p.m.
Last Modified :
April 15, 2026, 3:03 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update ONNX to version 1.21.0 or later.
- Verify the ONNX version is updated.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-34446.
| URL | Resource |
|---|---|
| https://github.com/onnx/onnx/commit/4755f8053928dce18a61db8fec71b69c74f786cb | Patch |
| https://github.com/onnx/onnx/security/advisories/GHSA-cmw6-hcpp-c6jp | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-34446 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-34446
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-34446 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-34446 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 15, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N Added CPE Configuration OR *cpe:2.3:a:linuxfoundation:onnx:*:*:*:*:*:*:*:* versions up to (excluding) 1.21.0 Added Reference Type GitHub, Inc.: https://github.com/onnx/onnx/commit/4755f8053928dce18a61db8fec71b69c74f786cb Types: Patch Added Reference Type GitHub, Inc.: https://github.com/onnx/onnx/security/advisories/GHSA-cmw6-hcpp-c6jp Types: Vendor Advisory -
New CVE Received by [email protected]
Apr. 01, 2026
Action Type Old Value New Value Added Description Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to version 1.21.0, there is an issue in onnx.load, the code checks for symlinks to prevent path traversal, but completely misses hardlinks because a hardlink looks exactly like a regular file on the filesystem. This issue has been patched in version 1.21.0. Added CVSS V3.1 AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N Added CWE CWE-22 Added CWE CWE-61 Added Reference https://github.com/onnx/onnx/commit/4755f8053928dce18a61db8fec71b69c74f786cb Added Reference https://github.com/onnx/onnx/security/advisories/GHSA-cmw6-hcpp-c6jp