CVE-2021-29939: Stackvector Project Stackvector

High severity, CVSS 7.3. EPSS: 1% chance of exploitation in the next 30 days.

An issue was discovered in the stackvector crate through 2021-02-19 for Rust. There is an out-of-bounds write in StackVec::extend if size_hint provides certain anomalous data.

Affected products

• Stackvector Project Stackvector: before 1.0.9 (fixed in 1.0.9)

Published 2021-04-01. Last modified 2026-06-17.