CVE-2021-43790: Use After Free in lucet

Published Nov 29, 2021
·
Updated

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.

Affected Software

1 affected component
bytecodealliance Lucet Rust<=0.6.1

Event History

Nov 29, 2021
CVE Published
via MITRE·11:55 PM
Data Sourced
via MITRE·11:55 PM
DescriptionSeverityWeakness
Nov 30, 2021
Data Sourced
via NVD·12:15 AM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is CVE-2021-43790?

CVE-2021-43790 is a vulnerability in the Lucet runtime that allows a use-after-free in an Instance object, leading to memory corruption and other related issues.

2

What is the severity of CVE-2021-43790?

CVE-2021-43790 has a severity score of 8.1 (high).

3

Which software versions are affected by CVE-2021-43790?

Versions up to and including 0.6.1 of Lucet published on crates.io are affected by CVE-2021-43790.

4

How can I fix CVE-2021-43790?

To fix CVE-2021-43790, update Lucet to a version higher than 0.6.1.

5

Where can I find more information about CVE-2021-43790?

You can find more information about CVE-2021-43790 in the references provided: [link](https://crates.io/crates/lucet-runtime), [link](https://github.com/bytecodealliance/lucet/commit/7c7757c772fb709c61b1442bcc1e1fbee97bf4a8), [link](https://github.com/bytecodealliance/lucet/security/advisories/GHSA-hf79-8hjp-rrvq).

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