Use After Free in Bytecodealliance Lucet

CVE-2021-43790

Lucet is a native WebAssembly compiler and runtime. There is a bug in the main branch of `lucet-runtime` affecting all versions published to crates.io that allows a use-after-free in an Instance object that could result in memory corruption, data race, or other related issues. This bug was introduced early in the development of Lucet and is present in all releases. As a result of this bug, and dependent on the memory backing for the Instance objects, it is possible to trigger a use-after-free when the Instance is dropped. Users should upgrade to the main branch of the Lucet repository. Lucet no longer provides versioned releases on crates.io. There is no way to remediate this vulnerability without upgrading.

Vulnerability class: Use-After-Free

EPSS: 0.016 (72.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-43790?
CVE-2021-43790 is a high-severity vulnerability in Bytecodealliance Lucet, classified under Use After Free. CVSS score: 8.5/10. Published 2021-11-30.
How severe is CVE-2021-43790?
High severity. CVSS v3 base score is 8.5 out of 10.