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.
Fix
Patch, vendor advisory and mitigation references on NVD 4
- https://github.com/ray-project/ray/pull/63469 Issue Tracking, Patch
- https://github.com/ray-project/ray/pull/63470 Issue Tracking, Patch
- https://github.com/ray-project/ray/security/advisories/GHSA-hhrp-gw25-jr43 Exploit, Mitigation, Patch, Vendor Advisory
- https://github.com/ray-project/ray/security/advisories/GHSA-hhrp-gw25-jr43 Exploit, Mitigation, Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 8.6 · anyscaleNVD modified 2026-10-08 16:17
Affected (CPE criteria) 1
cpe:2.3:a:anyscale:ray:*:*:*:*:*:*:*:*
References 6
- https://github.com/ray-project/ray/pull/63469 Issue Tracking, Patch
- https://github.com/ray-project/ray/pull/63470 Issue Tracking, Patch
- https://github.com/ray-project/ray/releases/tag/ray-2.56.0 Product, Release Notes
- https://github.com/ray-project/ray/security/advisories/GHSA-hhrp-gw25-jr43 Exploit, Mitigation, Patch, Vendor Advisory
- https://www.vulncheck.com/advisories/ray-unsafe-deserialization-rce-via-webdataset-reader Third Party Advisory
- https://github.com/ray-project/ray/security/advisories/GHSA-hhrp-gw25-jr43 Exploit, Mitigation, Patch, Vendor Advisory