CVE-2026-119131 Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via wasi-http
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-119131?
CVE-2026-119131 is a medium-severity vulnerability in bytecodealliance wasmtime, published on 29 Oct 2026.
Official description
Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 contains a denial of service vulnerability in wasmtime-wasi-http that lets guests crash the host by sending long request URLs. Guests can use set-path-with-query with a '?' after byte 65535, overflowing a u16 index in the http crate and triggering a host panic.
Weakness: CWE-190
Which versions are affected by CVE-2026-119131?
1 open source package ship an affected version, including wasmtime-wasi-http.
| Package | Affected | Fixed in |
|---|---|---|
wasmtime-wasi-http crates.io | From 46.0.0 | 48.0.6, 49.0.3 |
How do I fix CVE-2026-119131?
Upgrade wasmtime-wasi-http to a fixed version for your release line: 48.0.6 or 49.0.3.
Is CVE-2026-119131 being exploited?
There is no known exploitation of CVE-2026-119131 in the wild and no public exploit code.
Sources
Also known as GHSA-9vvr-fpgq-p9gc, GHSA-w36r-2hch-9xp9, RUSTSEC-2026-0351.