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OpenAdvisories
Medium · 4.8 CVE-2026-119132 EUVD-2026-113199GHSA-54p9-vhhq-8f7qGHSA-hv43-9665-59p4RUSTSEC-2026-0360

Wasmtime 49.0.0 before 49.0.3 Host Panic via Overlapping String Transcode in Fused Adapter

Published Oct 29, 2026 · Updated Nov 3, 2026 · Assigned by VulnCheck

Description

Wasmtime from 49.0.0 before 49.0.3 contains a denial-of-service vulnerability that allows a WebAssembly guest to trigger a host panic by transcoding overlapping strings in fused adapters. Attackers can make a same-instance component-to-component call transferring a string whose source and destination alias each other, crashing the host instead of raising a trap.

Affected products

VendorProductAffectedFixed
bytecodealliance wasmtime 49.0.0 – < 49.0.3 49.0.3

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Ubuntu 26.10 rust-wasmtime No fix yet —
Ubuntu 26.04 LTS rust-wasmtime No fix yet —
Ubuntu 24.04 LTS rust-wasmtime No fix yet —

Affected packages

EcosystemPackageAffectedFixedRecord
crates.io wasmtime >= 49.0.0, < 49.0.3 49.0.3 RUSTSEC-2026-0360

References