Description
wasmtime-wasi in Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 re-appends a trailing slash to rename source paths, causing renameat on macOS and FreeBSD hosts to follow directory symlinks. A guest with sandbox write access can rename a relative symlink such as "up/" to move host directories into its sandbox and read or write them.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| bytecodealliance | wasmtime | < 36.0.18, 37.0.0 – < 48.0.6, 49.0.0 – < 49.0.3 | 36.0.18 |
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 | 36.0.20+dfsg-1 | — |
| Debian 13 | rust-wasmtime | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| crates.io | wasmtime-wasi | >= 0.0.0-0, < 36.0.18 · >= 37.0.0, < 48.0.6 · >= 49.0.0, < 49.0.3 | 36.0.18, 48.0.6, 49.0.3 | RUSTSEC-2026-0352 |