{"cve":"CVE-2020-35917","nvd":{"published":"2020-12-31T09:15:15.833","modified":"2026-06-17T03:14:36.110","status":"Modified","description":"An issue was discovered in the pyo3 crate before 0.12.4 for Rust. There is a reference-counting error and use-after-free in From<Py<T>>.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-416"],"references":["https://rustsec.org/advisories/RUSTSEC-2020-0074.html","https://rustsec.org/advisories/RUSTSEC-2020-0074.html"],"products":["pyo3_project:pyo3"],"source":"nvd","synced_at":"2026-10-19T21:12:09.559580076+00:00"},"epss":{"cve":"CVE-2020-35917","score":0.00393,"percentile":0.33484,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-2vx6-fcw6-hpr6","url":"https://osv.dev/vulnerability/GHSA-2vx6-fcw6-hpr6","summary":"Reference counting error in pyo3","modified":"2023-11-08T04:03:39.286074Z","packages":[{"ecosystem":"crates.io","name":"pyo3","purl":"pkg:cargo/pyo3","ranges":[">=0.12.0 <0.12.4"],"fixed":["0.12.4"]}]},{"id":"RUSTSEC-2020-0074","url":"https://osv.dev/vulnerability/RUSTSEC-2020-0074","summary":"Reference counting error in `From<Py<T>>`","modified":"2023-11-08T04:03:39.286074Z","packages":[{"ecosystem":"crates.io","name":"pyo3","purl":"pkg:cargo/pyo3","ranges":[">=0.12.0 <0.12.4"],"fixed":["0.12.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}