CVE-2026-115889 (GCVE-0-2026-115889)
Vulnerability from cvelistv5
Published
2026-10-23 21:23
Modified
2026-10-26 17:42
Severity ?
CWE
  • CWE-197 - Numeric Truncation Error
  • CWE-843 - Access of Resource Using Incompatible Type ('Type Confusion')
Summary
Wasmtime is a runtime for WebAssembly. Prior to 36.0.19 and 43.0.0, the Cranelift compiler backend bit-packs SSA value indices in a way that can silently overflow in release builds when compiling a sufficiently large or specially crafted Wasm function with many SSA values. The overflow can make Cranelift reference incorrect IR values, causing arbitrary miscompilation, type confusion, and other attacker-controlled effects that may escape the Wasm sandbox on any architecture using the default Cranelift backend. This issue is fixed in versions 36.0.19 and 43.0.0.
Impacted products
Vendor Product Version
bytecodealliance wasmtime Version: < 36.0.19
Version: >= 37.0.0, < 43.0.0
Create a notification for this product.
Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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