Use After Free Affecting wasmcloud package, versions <2.0.4-r0


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.01% (2nd percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-WASMCLOUD-16122140
  • published22 Apr 2026
  • disclosed9 Apr 2026

Introduced: 9 Apr 2026

NewCVE-2026-34983  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Chainguard wasmcloud to version 2.0.4-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream wasmcloud package and not the wasmcloud package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

Wasmtime is a runtime for WebAssembly. In 43.0.0, cloning a wasmtime::Linker is unsound and can result in use-after-free bugs. This bug is not controllable by guest Wasm programs. It can only be triggered by a specific sequence of embedder API calls made by the host. Specifically, the following steps must occur to trigger the bug clone a wasmtime::Linker, drop the original linker instance, use the new, cloned linker instance, resulting in a use-after-free. This vulnerability is fixed in 43.0.1.

CVSS Base Scores

version 3.1