FKIE_CVE-2026-31221

Vulnerability from fkie_nvd - Published: 2026-05-12 16:16 - Updated: 2026-05-15 19:16
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Summary
PyTorch-Lightning versions 2.6.0 and earlier contain an insecure deserialization vulnerability (CWE-502) in the checkpoint loading mechanism. The LightningModule.load_from_checkpoint() method, which is commonly used to load saved model states, internally calls torch.load() without setting the security-restrictive weights_only=True parameter. This default behavior allows the deserialization of arbitrary Python objects via the Pickle module. A remote attacker can exploit this by providing a maliciously crafted checkpoint file, leading to arbitrary code execution on the victim's system when the file is loaded.
References
cve@mitre.orghttps://github.com/Lightning-AI/pytorch-lightningProduct
cve@mitre.orghttps://www.notion.so/CVE-2026-31221-35d1e1393188815f8db7c4fd08076639Exploit, Third Party Advisory
Impacted products
Vendor Product Version
lightningai pytorch_lightning *
To clipboard 

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  "id": "CVE-2026-31221",
  "lastModified": "2026-05-15T19:16:57.333",
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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.