Always-Incorrect Control Flow Implementation Affecting wasmcloud package, versions <2.0.4-r0


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.02% (4th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-WASMCLOUD-16122149
  • published22 Apr 2026
  • disclosed9 Apr 2026

Introduced: 9 Apr 2026

NewCVE-2026-34946  (opens in a new tab)
CWE-670  (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. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler contains a vulnerability where the compilation of the table.fill instruction can result in a host panic. This means that a valid guest can be compiled with Winch, on any architecture, and cause the host to panic. This represents a denial-of-service vulnerability in Wasmtime due to guests being able to trigger a panic. The specific issue is that a historical refactoring changed how compiled code referenced tables within the table.* instructions. This refactoring forgot to update the Winch code paths associated as well, meaning that Winch was using the wrong indexing scheme. Due to the feature support of Winch the only problem that can result is tables being mixed up or nonexistent tables being used, meaning that the guest is limited to panicking the host (using a nonexistent table), or executing spec-incorrect behavior and modifying the wrong table. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1.

CVSS Base Scores

version 3.1