{"id":"CVE-2026-31221","details":"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.","aliases":["GHSA-75m9-98v2-hjpm"],"modified":"2026-07-08T08:05:02.440763081Z","published":"2026-05-12T00:00:00Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31221.json","cna_assigner":"mitre"},"references":[{"type":"WEB","url":"https://www.notion.so/CVE-2026-31221-35d1e1393188815f8db7c4fd08076639"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31221.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31221"},{"type":"PACKAGE","url":"https://github.com/Lightning-AI/pytorch-lightning"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/lightning-ai/pytorch-lightning","events":[{"introduced":"0"},{"last_affected":"854037098554a5fbf6ab7c66ae9617987e82911f"}],"database_specific":{"cpe":"cpe:2.3:a:lightningai:pytorch_lightning:*:*:*:*:*:python:*:*","source":"CPE_RANGE","extracted_events":[{"introduced":"0"},{"last_affected":"2.6.0"}]}}],"versions":["2.6.0","2.5.0.post0","2.5.0","2.5.0rc0","2.4.0","2.3.0","2.2.0","2.2.0.rc0","2.1.0","2.1.0.rc1","2.1.0.rc0","2.0.0","2.0.0rc0","1.9.0","1.9.0rc0","1.8.0","1.8.0rc2","1.8.0rc1","1.8.0rc0","app/0.6.0rc0","1.7.0","1.7.0rc1","1.7.0rc0","1.6.0","1.6.0rc1","1.6.0rc0","1.5.0","1.5.0rc1","1.5.0rc0","1.4.0","1.4.0rc2","1.4.0rc1","1.4.0rc0","1.3.0","1.3.0rc3","1.3.0rc2","1.3.0rc1","1.3.0rc0","1.2.0","1.2.0rc2","1.2.0rc1","1.1.0","1.1.0rc2","1.1.0rc1","1.0.4","1.0.3","1.0.2","1.0.1","1.0.0","0.10.0","0.9.0","0.8.5","0.8.4","0.8.3","0.8.2","0.8.1","0.8.0","0.7.6","0.7.5","0.7.4","0.7.3","0.7.2","0.7.1","0.7.0","0.6.0","0.5.2.1","0.5.2","0.5.1","0.5.0","0.4.9","0.4.7","0.4.6","0.4.5","0.4.4","0.4.3","0.4.2","0.4.1","0.4.0","0.2.1","0.2","0.1.2","0.1.1","0.0.2","0.0.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31221.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"}]}