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TI-2021-19597 Aliases CVE-2021-43790GHSA-hf79-8hjp-rrvq

Use After Free in lucet

Priority MEDIUM 40CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-416 and the CVSS impact.

Summary

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.

Why it matters now

EPSS 0.01617 76th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
bytecodealliancelucetup to 0.6.1—No fix listedCNA
—lucet-runtime (crates.io)up to 0.6.1—No fix listedGHSA-hf79-8hjp-rrvq
  • lucet Vendorbytecodealliance Affected up to 0.6.1 Fixed in — No fix listed CNA
  • lucet-runtime (crates.io) Vendor— Affected up to 0.6.1 Fixed in — No fix listed GHSA-hf79-8hjp-rrvq

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:bytecodealliance:lucet:*:*:*:*:*:rust:*:*up to 0.6.1Vulnerablebytecodealliance
  • cpe:2.3:a:bytecodealliance:lucet:*:*:*:*:*:rust:*:* Versions up to 0.6.1 Vulnerable ·bytecodealliance

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-43790
  2. 2026-10-03 Alias added: GHSA-hf79-8hjp-rrvq

References

Exploit 1

Patch 1

Advisory 2

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences