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  4. CVE 2021 39216 multiple vulnerabilities in wasmtime
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Back to active CVEs
Medium · CVSS 6.3CVE-2021-39216GHSA-4873-36H9-WV49

Multiple Vulnerabilities in WasmtimeCVE-2021-39216

Answer in brief

CVE-2021-39216 records a Medium severity (CVSS 6.3) vulnerability in Multiple Vulnerabilities in Wasmtime. The current sources do not mark it as known exploited. The current feed maps wasmtime (crates.io). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 17, 2021Updated Nov 9, 2026Source checked Nov 9, 2026First seen by HOL Nov 9, 2026Material review Nov 9, 2026
Upstream Advisory

Key facts

Risk
Medium · CVSS 6.3
Exploitation
Not marked as known exploited
Affected software
1 mapped package or product
Fix availability
Available

Why this deserves its current priority

CVSS is 6.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps wasmtime (crates.io). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
wasmtimecrates.io>=0.0.0-0 <0.30.00.30.0

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for wasmtime.
  2. 2Review the reported fix. Update wasmtime to 0.30.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Sep 17, 2021

    Evidence: source:osv:source_dates:source-dates:record

  2. Source modified

    Nov 9, 2026

    Evidence: source:osv:source_dates:source-dates:record

  3. First seen by HOL

    Nov 9, 2026

Sources and claim methodology

  • Source referencecrates.io
  • Source referencerustsec.org
Upstream source description

* [Use after free passing `externref`s to Wasm in Wasmtime](https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-v4cp-h94r-m7xf) * [Out-of-bounds read/write and invalid free with `externref`s and GC safepoints in Wasmtime](https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-4873-36h9-wv49) * [Wrong type for `Linker`-define functions when used across two `Engine`s](https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-q879-9g95-56mx)

Quoted source text, attributed separately from HOL analysis.

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
Not reported
Source
OSV
Source checked
Nov 9, 2026
References
2 linked sources
Open source record