CVE-2026-31221
📛 CVE Title
CVE-2026-31221
Description
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- mitre
- CVSS severity
- high
- CVSS score
- 7.8 / 10
- CVSS vector
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H- Effective score
- 7.8 / 10 HIGH source: CNA overview
- CWE(s)
- —
- Reserved
- 2026-03-09
- Published
- 2026-05-12 00:00 UTC
- Last updated
- 2026-05-15 18:05 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/31xxx/CVE-2026-31221.json
- Linked Threat
- CVE-2026-31221 — CVE-2026-31221
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-12 16:16:14 UTC
- NVD last modified
- 2026-05-15 19:16:57 UTC
- NVD CVSS v3.1
- 7.8 / 10 HIGH source: nvd@nist.gov
- NVD CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H- Exploitability subscore
- 1.8 / 10
- Impact subscore
- 5.9 / 10
- EPSS score
- 0.0019 (probability of exploitation in next 30 days)
- EPSS percentile
- 40.66% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD-assigned CWE(s):
CWE-502
(differs from the CNA list above)
NVD / KEV / EPSS data refreshed 2026-05-25 03:34 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-29505 - Assigner
- mitre
- Published
- May 12, 2026, 12:00:00 AM
- Updated
- May 15, 2026, 6:05:39 PM
- EUVD base score (CVSS 3.1)
-
8.8 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EUVD-reported EPSS
- 0.1900
- Vendors
- n/a
- Products
-
n/a (n/a)
ENISA description: 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.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| n/a | n/a |
n/a (affected)
|
— |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:lightningai:pytorch_lightning:*:*:*:*:*:python:*:*
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
Web references (5)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://github.com/Lightning-AI/pytorch-lightning tenable:github.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-31221 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-31221 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
- https://www.notion.so/CVE-2026-31221-35d1e1393188815f8db7c4fd08076639 tenable:www.notion.so
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/Lightning-AI/pytorch-lightning cve@mitre.org Product
- https://www.notion.so/CVE-2026-31221-35d1e1393188815f8db7c4fd08076639 cve@mitre.org ExploitThird Party Advisory
Remediations (20)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:app.opencve.io
Remediation No vendor fix or workaround currently provided. OpenCVE Recommended Actions Apply any Microsoft security update that addresses CVE - 2026 -32202, obtained through Windows Update or the Microsoft Update Catalog, as soon as it is released.
2026-05-23 21:45 UTC -
web:epatch.pa.gov
Why does PATCH exist? Its purpose is to better enable the public to obtain criminal history record checks. The repository was created and is maintained in accordance with Pennsylvania's Criminal History Information Act contained in Chapter 91 of Title 18, Crimes Code. This Act also directs the Pennsylvania State Police (PSP) to disseminate criminal history data to criminal justice agencies ...
2026-05-23 21:45 UTC -
web:forums.ea.com
About This Thread This thread tracks Sims 4 mods and CC that have been "broken" or made obsolete by game update1.124, May 12, 2026 , and the May 21 hotfix, or declared unsupported by their creators. It also tracks updated game mods, important updates to custom content, general news from/about creators, and new bugfix mods.
2026-05-23 21:45 UTC -
web:msrc.microsoft.com
Security Update Guide - Microsoft Security Response Center
2026-05-23 21:45 UTC -
web:playvalorant.com
VALORANT Patch Notes 11.10 The Harbor Rework is here! Along with QoL updates, balance updates to Clove, and bug fixes.
2026-05-23 21:45 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's April 2026 Patch Tuesday with security updates for 167 flaws, including 2 zero-day vulnerabilities.
2026-05-23 21:45 UTC -
web:www.oracle.com
Oracle Critical Patch Update Advisory - January 2026 Description A Critical Patch Update is a collection of patches for multiple security vulnerabilities. These patches address vulnerabilities in Oracle code and in third party components included in Oracle products. These patches are usually cumulative, but each advisory describes only the security patches added since the previous Critical ...
2026-05-23 21:45 UTC -
web:www.securityweek.com
Microsoft's latest Patch Tuesday updates fix 165 vulnerabilities, including a SharePoint zero-day that has been exploited in the wild. The exploited SharePoint Server vulnerability is tracked as CVE - 2026 -32201 and it has been described as a spoofing issue. Microsoft assigned it an 'important ...
2026-05-23 21:45 UTC -
web:www.techrepublic.com
Adobe patches a critical PDF flaw exploited for months, allowing attackers to bypass sandbox protections and deliver malware. Users urged to update now.
2026-05-23 21:45 UTC -
web:www.tenable.com
Microsoft patched 163 CVEs in April including two zero-day vulnerabilities in SharePoint and Microsoft Defender. CVE - 2026 -32201 was exploited in the wild.
2026-05-23 21:45 UTC -
web:carthageelectronics.com
Status: Actively exploited — CISA KEV listed — patch by May 12, 2026 What Happened On April 28, 2026 , CISA added CVE - 2026 -32202 to its Known Exploited Vulnerabilities (KEV) catalog with a federal remediation deadline of May 12, 2026 . This vulnerability is the result of an incomplete patch Microsoft released in February for CVE - 2026 -21510.
2026-05-26 02:53 UTC -
web:cybersecuritynews.com
Microsoft released its March 2026 Patch Tuesday security update on March 10, 2026 , addressing 78 vulnerabilities across Windows, Microsoft Office, Azure, SQL Server, and .NET. The update includes one actively exploited zero-day vulnerability and multiple Critical-rated flaws demanding immediate attention from security teams. The most urgent fix this month is CVE - 2026 -21262, the sole zero-day ...
2026-05-26 02:53 UTC -
web:nvd.nist.gov
Information Technology Laboratory National Vulnerability Database Vulnerabilities
2026-05-26 02:53 UTC -
web:www.cisa.gov
Linux Kernel Incorrect Resource Transfer Between Spheres Vulnerability This type of vulnerability is a frequent attack vector for malicious cyber actors and poses significant risks to the federal enterprise. Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the KEV Catalog as a living list of known Common Vulnerabilities and ...
2026-05-26 02:53 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-26 02:53 UTC -
web:www.crowdstrike.com
Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.
2026-05-26 02:53 UTC -
web:www.cve.org
At cve .org, we provide the authoritative reference method for publicly known information-security vulnerabilities and exposures
2026-05-26 02:53 UTC -
web:www.microsoft.com
Security Update Guide Notifications Microsoft's free Security Update Guide Notifications provide links to security-related software updates and notification of re-released security updates. These notifications are sent via email throughout the month as needed.
2026-05-26 02:53 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-05-26 02:53 UTC -
web:www.penligent.ai
Second, chipset and OEM dependencies make remediation slower and messier than software-only patching. Google's bulletin explains the two Android patch levels for March 2026 and clarifies that devices with security patch levels of 2026 -03-01 or 2026 -03-05 are protected against the associated issues, depending on applicable components.
2026-05-26 02:53 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-31221.json.
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