CVE-2026-118688 Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 Sandbox Escape via Symlink Rename
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-118688?
CVE-2026-118688 is a high-severity vulnerability in bytecodealliance wasmtime, published on 28 Oct 2026.
Official 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.
Weakness: CWE-61
Which versions are affected by CVE-2026-118688?
1 open source package ship an affected version, including wasmtime-wasi.
| Package | Affected | Fixed in |
|---|---|---|
wasmtime-wasi crates.io | From 0.0.0-0 | 36.0.18, 48.0.6, 49.0.3 |
How do I fix CVE-2026-118688?
Upgrade wasmtime-wasi to a fixed version for your release line: 36.0.18, 48.0.6 or 49.0.3.
Is CVE-2026-118688 being exploited?
There is no known exploitation of CVE-2026-118688 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-118688, GHSA-63fr-xrxj-8wrx, GHSA-m9f7-9w4p-gv38, RUSTSEC-2026-0352.