cvedb.io
CVE-2026-35186
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2026-04-09T19:16:25.343 · Last modified 2026-06-17T10:40:10.663

Summary

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 backend contains a bug where translating the table.grow operator causes the result to be incorrectly typed. For 32-bit tables this means that the result of the operator, internally in Winch, is tagged as a 64-bit value instead of a 32-bit value. This invalid internal representation of Winch's compiler state compounds into further issues depending on how the value is consumed. The primary consequence of this bug is that bytes in the host's address space can be stored/read from. This is only applicable to the 16 bytes before linear memory, however, as the only significant return value of table.grow that can be misinterpreted is -1. The bytes before linear memory are, by default,

Affected products

bytecodealliance — wasmtime

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.