CVE-2026-41486: Ray Ray Data remote code execution via Parquet deserialization

CVE-2026-41486 · Severity: high · CVSS 8.8 · Published 2026-05-08

Ray is an open-source AI compute engine used to scale machine learning workloads. A vulnerability in its data processing component allows an attacker to execute malicious code on a system by providing a specially crafted Parquet data file. This could lead to a full system compromise or unauthorized access to sensitive AI models and datasets whenever the application attempts to read the malicious file.

Technologies: ray (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-41486 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-41486 being exploited in the wild.
How severe is CVE-2026-41486?
High severity, with a CVSS score of 8.8, published 8 May 2026.
Which products and versions are affected?
ray (PyPI) >= 2.49.0, < 2.55.0, ECOSYSTEM:introduced=0,last_affected=2.54.0, ECOSYSTEM:introduced=2.49.0,fixed=2.55.0; ve-ray (PyPI) ECOSYSTEM:introduced=0,last_affected=2.54.0.
Is there a fix for CVE-2026-41486?
Yes. ray (PyPI): upgrade to 2.55.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-41486 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-41486?
Check whether you run ray (PyPI) or ve-ray (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • ray (PyPI): upgrade to 2.55.0 or later
    pip install "ray>=2.55.0"

Technical details

Ray Data registers custom Arrow extension types (such as ray.data.arrow_tensor) globally in PyArrow. When PyArrow reads a Parquet file containing these types, it invokes __arrow_ext_deserialize__ on the field's metadata. In affected versions, Ray's implementation of this method passes the metadata bytes directly to cloudpickle.loads() without validation. This allows for arbitrary code execution during the schema parsing phase, even before any actual row data is read. The vulnerability affects any process using Ray Data that reads Parquet files, including via pandas or pyarrow directly. The fix in version 2.55.0 switches the default deserialization to JSON and makes cloudpickle opt-in via an environment variable.

Affected products

  • Ray Project Ray 2.49.0 to 2.54.0

Identifiers

  • CVE-2026-41486
  • GHSA-mw35-8rx3-xf9r
  • PYSEC-2026-2272
  • PYSEC-2026-2296

Timeline

  • 2026-03-25: patched: Fix merged into master branch
  • 2026-04-15: advisory: Release of version 2.55.0
  • 2026-04-21: disclosed: Security advisory published on GitHub
  • 2026-05-08: advisory: NVD publication date

References

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