Disclosure summary
Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epoch_deadline_callback or continues using a Store after cancellation or a trap. A cancelled non-nullable table growth can leave null elements, linear-memory growth during memory.copy can invalidate retained raw pointers, and callback-triggered garbage collection during array.copy can invalidate GC pointers, resulting in a crash, invalid memory access, or GC heap corruption. Embeddings whose callbacks only access the host data in Store, and embeddings that discard a Store after timeout or epoch deadline, are not affected. This issue is fixed in versions 46.0.2 and 47.0.3.
Source-reported weakness categories
CWE-362
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
GitHub Reviewed Security Advisories · GHSA-2hw9-mc66-jc2q
Open original source · Updated Oct 02, 2026
Wasmtime: Preemption and traps during bulk operations enable breaking internal VM state
Source severity: LOW / 2
| Ecosystem | Package | Affected range | First patched |
|---|---|---|---|
| rust | wasmtime | >= 46.0.0, < 46.0.2 | 46.0.2 |
| rust | wasmtime | >= 47.0.0, < 47.0.3 | 47.0.3 |
NIST National Vulnerability Database · NVD-CVE-2026-104855
Open original source · Updated Oct 02, 2026
Only CPE matches marked vulnerable=true are indexed. AND/OR platform conditions must be checked in the original NVD record.
Original records & references
- NIST NVD record
- CVE Program record
- github.com
- github.com
- github.com
- github.com
- github.com
- github.com
- github.com
- github.com
- github.com
PUBLISHED 2026-10-02T14:17:02-04:00
MODIFIED 2026-10-02T14:17:02-04:00
INGESTED 2026-10-06T11:45:30-04:00