EUVD-2022-6243Published

Wasmtime is a standalone runtime for WebAssembly. There is a bug in the Wasmtime's code generator, Cranelift, where functions using reference types may be incorrectly missing metadata required for runtime garbage collection. This means that…

Exact source revision recorded 1 Nov 2026 21:02:15 UTC. It does not establish the source's current position. Latest evidence.

Recorded JSON

euvd · EUVD-2022-6243

Published

Wasmtime is a standalone runtime for WebAssembly. There is a bug in the Wasmtime's code generator, Cranelift, where functions using reference types may be incorrectly missing metadata required for runtime garbage collection. This means that if a GC happens at runtime then the GC pass will mistakenly think these functions do not have live references to GC'd values, reclaiming them and deallocating them. The function will then subsequently continue to use the values assuming they had not been GC'd, leading later to a use-after-free. This bug was introduced in the migration to the `regalloc2` register allocator that occurred in the Wasmtime 0.37.0 release on 2022-05-20. This bug has been patched and users should upgrade to Wasmtime version 0.38.2. Mitigations for this issue can be achieved by disabling the reference types proposal by passing `false` to `wasmtime::Config::wasm_reference_types` or downgrading to Wasmtime 0.36.0 or prior.

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Jul 20, 2022, 10:30:16 PM

dateUpdated: Apr 23, 2025, 5:57:59 PM

1 related source bulletins · separate from aliases

msrc_CVE-2022-31146: Use after free in Wasmtime

CVE-2022-31146

Source published: Jul 20, 2022, 10:30:16 PM (timezone not stated)
Source modified: Apr 23, 2025, 5:57:59 PM (timezone not stated)
Observed here: 1 Nov 2026 21:02:15 UTC
Source terms: ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 6.4 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L