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
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| 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.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| crates.io | wasmtime | >= 49.0.0, < 49.0.3 | 49.0.3 | RUSTSEC-2026-0360 |