CVE-2020-35917: PYO3 Project PYO3

Medium severity, CVSS 5.5. EPSS: 0.4% chance of exploitation in the next 30 days.

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>>.

Affected products

• PYO3 Project PYO3: before 0.12.4 (fixed in 0.12.4)

Published 2020-12-31. Last modified 2026-06-17.