CVE-2026-126409
Wasmtime 47.0.0 before 48.0.8 Cross-Engine Type Confusion via StructType Supertype
CVSS Score
2.0
EPSS Score
0.0%
EPSS Percentile
0th
Wasmtime 47.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 contains a cross-engine type confusion vulnerability because StructType::with_finality_and_supertype does not validate that the supplied supertype belongs to the same Engine. Embedders using multiple engines that create a GC struct type with another engine's supertype can trigger runtime panics or GC heap corruption, causing denial of service; guest WebAssembly cannot trigger it.
| CWE | CWE-843 |
| Vendor | bytecodealliance |
| Product | wasmtime |
| Published | Nov 13, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:L Attack Vector
Network
Attack Complexity
High
Privileges Required
High
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Affected Versions
bytecodealliance / wasmtime
47.0.0 < 48.0.8
bytecodealliance / wasmtime
49.0.0 < 49.0.5
bytecodealliance / wasmtime
50.0.0 < 50.0.1