Description

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime contains a possible panic which can happen when a flags-typed component model value is lifted with the Val type. If bits are set outside of the set of flags the component model specifies that these bits should be ignored but Wasmtime will panic when this value is lifted. This panic only affects wasmtime's implementation of lifting into Val, not when using the flags! macro. This additionally only affects flags-typed values which are part of a WIT interface. This has the risk of being a guest-controlled panic within the host which Wasmtime considers a DoS vector. This vulnerability is fixed in 24.0.7, 36.0.7, 42.0.2, and 43.0.1.

INFO

Published Date :

2026-04-09T18:36:51.370Z

Last Modified :

2026-04-13T20:15:23.994Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-34943 vulnerability.

Vendors Products
Bytecodealliance
  • Wasmtime
REFERENCES

CVSS Vulnerability Scoring System

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Detailed values of each vector for above chart.
Attack Vector
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User Interaction
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Confidentiality Impact
Integrity Impact
Availability Impact