CVE-2026-119133 Wasmtime 47.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Misaligned VMContext via Exception Tags
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-119133?
CVE-2026-119133 is a low-severity vulnerability in bytecodealliance wasmtime, published on 29 Oct 2026.
Official description
Wasmtime 47.0.0 before 48.0.6 and 49.0.0 before 49.0.3 contains a memory misalignment flaw in VMContext layout that causes undefined behavior when modules contain an odd number of exception tags. A WebAssembly module with an odd tag count misaligns subsequent host fields in embedders with exceptions enabled, although no exploitation path is currently known.
Weakness: CWE-758
Which versions are affected by CVE-2026-119133?
1 open source package ship an affected version, including wasmtime.
| Package | Affected | Fixed in |
|---|---|---|
wasmtime crates.io | From 47.0.0 | 48.0.6, 49.0.3 |
How do I fix CVE-2026-119133?
Upgrade wasmtime to a fixed version for your release line: 48.0.6 or 49.0.3.
Is CVE-2026-119133 being exploited?
There is no known exploitation of CVE-2026-119133 in the wild and no public exploit code.
Sources
Also known as GHSA-9283-62cg-q26h, GHSA-p79w-pv2r-29qp, RUSTSEC-2026-0364.