CVE-2026-57516

Ray < 2.56.0 Unsafe Deserialization RCE via WebDataset Reader

Published Jul 1, 2026 CVSS 4.0 · 8.6 High EPSS 1.1% KEV · Not listed
Description
Ray prior to 2.56.0 contains an unsafe deserialization vulnerability in the WebDataset reader that allows attackers to achieve remote code execution by supplying a malicious tar archive to the read_webdataset() function. The _default_decoder() function in webdataset_datasource.py unconditionally calls pickle.loads() on tar entries with .pkl/.pickle extensions and torch.load() with weights_only=False on .pt/.pth entries, executing arbitrary code inside Ray remote workers on every worker that processes the malicious archive.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-hhrp-gw25-jr43 Ray: Arbitrary code execution via ray.data.read_webdataset default decoder: pickle.loads(value) and torch.load(weights_only=False)
History
Type Values Removed Values Added
CPEs cpe:2.3:a:anyscale:ray:*:*:*:*:*:*:*:*
Type Values Removed Values Added
First Time appeared Anyscale
Anyscale ray
Vendors & Products Anyscale
Anyscale ray
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Ray prior to 2.56.0 contains an unsafe deserialization vulnerability in the WebDataset reader that allows attackers to achieve remote code execution by supplying a malicious tar archive to the read_webdataset() function. The _default_decoder() function in webdataset_datasource.py unconditionally calls pickle.loads() on tar entries with .pkl/.pickle extensions and torch.load() with weights_only=False on .pt/.pth entries, executing arbitrary code inside Ray remote workers on every worker that processes the malicious archive.
Title Ray < 2.56.0 Unsafe Deserialization RCE via WebDataset Reader
Weaknesses CWE-502
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 8.6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Nov 8, 2026, 2:06 PM
Reserved
Jun 24, 2026, 3:58 PM
Status
Analyzed
Published
Jul 1, 2026, 5:16 PM
Modified
Oct 25, 2026, 5:10 PM