Out-of-bounds Read in Bytecodealliance Wasmtime

CVE-2026-34987

Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime with its Winch (baseline) non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-…

Vulnerability class: Buffer Overflow

EPSS: 0.001 (18.3th percentile) — read the EPSS interpretation.

Affected products

Bytecodealliance Wasmtime — versions >= 25.0.0, < 36.0.7, >= 37.0.0, < 42.0.2, >= 43.0.0, < 44.0.1

Weakness classification (CWE)

References

https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83 (x_refsource_CONFIRM)