CVE-2026-115889
Mở trang đầy đủCVSS 9.9 CRITICAL RCE
Wasmtime: Bit-packing in Cranelift compiler causes silent overflow and miscompilation
Mô tả
Summary
In Wasmtime prior to v43, the Cranelift compiler backend bit-packs its SSA value indices in a way that can result in silent overflow in release builds, and result in incorrect value references in the IR resulting in arbitrary miscompilation. A very large Wasm function body, or one that is specially crafted to use many SSA values, can use this to force type-confusion or other arbitrary side-effects and escape the sandbox.
Cranelift was changed in Wasmtime v43 to use a full u32 index, with checks if that limit is exceeded, and so is no longer susceptible to this bug.
Impact
A Wasmtime engine with default settings (using the Cranelift backend) on any architecture/platform could experience a sandbox escape from a specially-crafted Wasm module.
Patches
Wasmtime v36.0.19 has been released which fixes this issue.
Điểm và phân loại
- CVSS
- 9.9 CRITICAL v3.1
- Nguồn điểm
- GitHub Advisory
- Mức độ (theo nguồn)
- CRITICAL
- EPSS
- 0.45%
Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Ảnh hưởng
| Package | Bản bị ảnh hưởng | Bản đã sửa |
|---|---|---|
rust wasmtime |
< 36.0.19 |
36.0.19
|
rust wasmtime |
>= 37.0.0, < 43.0.0 |
43.0.0
|
Vì sao được giữ
- CVSS 9.9 >= 8.0
Loại tác động
- RCE
- CWE-843 + AV:N/I:H
Tham khảo
- https://github.com/advisories/GHSA-897f-g5gm-fmxm
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm
- https://github.com/bytecodealliance/wasmtime/pull/12613
- https://github.com/bytecodealliance/wasmtime/pull/14818
- https://github.com/bytecodealliance/wasmtime/commit/ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0
- https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa
- https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19
- https://github.com/bytecodealliance/wasmtime/releases/tag/v43.0.0
- https://rustsec.org/advisories/RUSTSEC-2026-0380.html