Incorrect Conversion between Numeric Types 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-16122143
  • published22 Apr 2026
  • disclosed9 Apr 2026

Introduced: 9 Apr 2026

NewCVE-2026-34945  (opens in a new tab)
CWE-681  (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 bug where a 64-bit table, part of the memory64 proposal of WebAssembly, incorrectly translated the table.size instruction. This bug could lead to disclosing data on the host's stack to WebAssembly guests. The host's stack can possibly contain sensitive data related to other host-originating operations which is not intended to be disclosed to guests. This bug specifically arose from a mistake where the return value of table.size was statically typed as a 32-bit integer, as opposed to consulting the table's index type to see how large the returned register could be. When combined with details about Wnich's ABI, such as multi-value returns, this can be combined to read stack data from the host, within a guest. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1.

CVSS Base Scores

version 3.1