Description
Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, On x86-64 platforms with SSE3 disabled Wasmtime's compilation of the f64x2.splat WebAssembly instruction with Cranelift may load 8 more bytes than is necessary. When signals-based-traps are disabled this can result in a uncaught segfault due to loading from unmapped guard pages. With guard pages disabled it's possible for out-of-sandbox data to be loaded, but this data is not visible to WebAssembly guests. This vulnerability is fixed in 24.0.7, 36.0.7, 42.0.2, and 43.0.1.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| bytecodealliance | wasmtime | < 24.0.7, >= 25.0.0, < 36.0.7, >= 37.0.0, < 42.0.2, >= 43.0.0, < 44.0.1 | — |
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.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | rust-wasmtime | 36.0.7+dfsg-1 | — |
| Debian 13 | rust-wasmtime | No fix yet | — |
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 25.10 | rust-wasmtime | No fix yet | — |
| Ubuntu 24.04 LTS | rust-wasmtime | No fix yet | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | wash | No fix yet | — |
| Wolfi rolling | wasmcloud | 2.0.4-r0 | — |
| Wolfi rolling | wizer | 11.0.3-r10 | — |
| Wolfi rolling | yara-x | 1.15.0-r2 | — |
| Wolfi rolling | zed | 0.228.0-r3 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| crates.io | wasmtime | < 24.0.7 | 24.0.7 | GHSA-qqfj-4vcm-26hv |
| crates.io | wasmtime | >= 25.0.0, < 36.0.7 | 36.0.7 | GHSA-qqfj-4vcm-26hv |
| crates.io | wasmtime | >= 37.0.0, < 42.0.2 | 42.0.2 | GHSA-qqfj-4vcm-26hv |
| crates.io | wasmtime | >= 43.0.0, < 43.0.1 | 43.0.1 | GHSA-qqfj-4vcm-26hv |
| crates.io | wasmtime | >= 0.0.0-0, < 24.0.7 · >= 25.0.0, < 36.0.7 · >= 37.0.0, < 42.0.2 · >= 43.0.0, < 43.0.1 | 24.0.7, 36.0.7, 42.0.2, 43.0.1 | RUSTSEC-2026-0087 |