PyTorch Lightning through 2.6.5, fixed in commit d710d68, contains a remote code execution vulnerability in the _load_state function that imports and executes attacker-controlled module names from checkpoint _instantiator hyperparameters. Attackers can craft malicious checkpoint files that bypass weights_only=True protections to execute arbitrary code when LightningModule.load_from_checkpoint is called.
CVE-2026-58659
HIGHPre-NVD 7.87.8
EchelonGraph scoreLOW confidence
This high-severity CVE scores 7.8 under the CNA's CVSS (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: cna:vulncheck
7.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: —CVSS: 7.8Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.8
- EG Score
- 7.8(low)
- EPSS
- —
- KEV
- Not listed
Published
July 15, 2026
Last Modified
July 15, 2026
Advisory Details (4)
Auto-updated Jul 15, 2026Upstream fix merged — awaiting tagged release. Sources: github_commit, github_pr.
generic
PyTorch Lightning Arbitrary Code Execution via _instantiator Hyperparameter | Advisories | VulnCheck
https://www.vulncheck.com/advisories/pytorch-lightning-arbitrary-code-execution-via-instantiator-hyperparametergithub_pr
fix(checkpoint): prevent arbitrary code execution via `_instantiator` in `load_from_checkpoint`
Fix merged in Lightning-AI/pytorch-lightning PR #21832 on 2026-07-14 — awaiting tagged release
https://github.com/Lightning-AI/pytorch-lightning/pull/21832generic
Arbitrary code execution via the `_instantiator` hyperparameter in `LightningModule.load_from_checkpoint` — defeats `torch.load(weights_only=True)` · Issue #21822 · Lightning-AI/pytorch-lightning · GitHub
https://github.com/Lightning-AI/pytorch-lightning/issues/21822github_commit
commit d710d689510d (Lightning-AI/pytorch-lightning)
Fix landed in Lightning-AI/pytorch-lightning commit d710d689510d — awaiting tagged release
https://github.com/Lightning-AI/pytorch-lightning/commit/d710d689510d50e800f53b3cd773cbca20b1f86fVendor Advisories for CVE-2026-58659(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 2× in last 7d / 2× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-15 17:29 UTCEG score recompute
- 2026-07-15 17:28 UTCMITRE cvelistV5first tracked
Frequently asked(4)
What is CVE-2026-58659?
CVE-2026-58659 is a high vulnerability published on July 15, 2026. PyTorch Lightning through 2.6.5, fixed in commit d710d68, contains a remote code execution vulnerability in the loadstate function that imports and executes attacker-controlled module names from checkpoint instantiator hyperparameters. Attackers can craft malicious checkpoint files that bypass…
When was CVE-2026-58659 disclosed?
CVE-2026-58659 was first published in the National Vulnerability Database on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-58659?
CVE-2026-58659 has a CVSS v3 base score of 7.8 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-58659?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-58659, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-58659
Is Your Infrastructure Affected by CVE-2026-58659?
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