Vulnerability · Published Oct 22, 2026 · Assigned by VulnCheck
CVE-2026-115393Wasmtime before 24.0.12, 25.0.0 before 36.0.13, 37.0.0 before 46.0.2, and 47.0.0 before 47.0.3 Cross-Engine Type Confusion
Low 3.8
In plain English
A low-severity out-of-bounds write in wasmtime from bytecodealliance. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 0% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Wasmtime before 24.0.12, 25.0.0 before 36.0.13, 37.0.0 before 46.0.2, and 47.0.0 before 47.0.3 contains a type confusion vulnerability because several Store APIs fail to validate that objects belong to the Store's Engine. Embedders mixing objects between Engines via Instance::new, StructRefPre::new, or Tag::new can trigger trampoline signature mismatches causing out-of-bounds stack writes, GC heap corruption, or panics.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:13 | rust-wasmtime | no fix listed | DEBIAN-CVE-2026-115393 |
| Debian:14 | rust-wasmtime | 36.0.13+dfsg-1 | DEBIAN-CVE-2026-115393 |
| Ubuntu:24.04:LTS | rust-wasmtime | no fix listed | UBUNTU-CVE-2026-115393 |
| Ubuntu:26.04:LTS | rust-wasmtime | no fix listed | UBUNTU-CVE-2026-115393 |
| Ubuntu:26.10 | rust-wasmtime | no fix listed | UBUNTU-CVE-2026-115393 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| bytecodealliance | wasmtime | 0 – before 24.0.1225.0.0 – before 36.0.1337.0.0 – before 46.0.247.0.0 – before 47.0.3 |
Weakness: CWE-787 · Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L