CVE-2021-38195: Parity LIBSECP256K1

Critical severity, CVSS 9.8. EPSS: 0.9% chance of exploitation in the next 30 days.

An issue was discovered in the libsecp256k1 crate before 0.5.0 for Rust. It can verify an invalid signature because it allows the R or S parameter to be larger than the curve order, aka an overflow.

Affected products

• Parity LIBSECP256K1: before 0.5.0 (fixed in 0.5.0)

Published 2021-08-08. Last modified 2026-06-17.