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TI-2022-13189 Aliases CVE-2022-31146GHSA-5fhj-g3p3-pq9g

Use After Free in Wasmtime

Priority MEDIUM 41CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-416 and the CVSS impact.

Summary

Wasmtime is a standalone runtime for WebAssembly. There is a bug in the Wasmtime's code generator, Cranelift, where functions using reference types may be incorrectly missing metadata required for runtime garbage collection. This means that if a GC happens at runtime then the GC pass will mistakenly think these functions do not have live references to GC'd values, reclaiming them and deallocating them. The function will then subsequently continue to use the values assuming they had not been GC'd, leading later to a use-after-free. This bug was introduced in the migration to the `regalloc2` register allocator that occurred in the Wasmtime 0.37.0 release on 2022-05-20. This bug has been patched and users should upgrade to Wasmtime version 0.38.2. Mitigations for this issue can be achieved by disabling the reference types proposal by passing `false` to `wasmtime::Config::wasm_reference_types` or downgrading to Wasmtime 0.36.0 or prior.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0125 69th percentileScored 2026-11-07
Fix Fixed wasmtime (bytecodealliance): 0.38.2, 0.85.2wasmtime (crates.io): 0.38.2+1 more product

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
bytecodealliancewasmtime0.37.0 to before 0.38.2; 0.84.0 to before 0.85.20.38.2, 0.85.2Patch availableCNA
—wasmtime (crates.io)0.37.0 to before 0.38.20.38.2Patch availableGHSA-5fhj-g3p3-pq9g
—cranelift-codegen (crates.io)0.84.0 to before 0.85.20.85.2Patch availableGHSA-5fhj-g3p3-pq9g
  • wasmtime Vendorbytecodealliance Affected 0.37.0 to before 0.38.2; 0.84.0 to before 0.85.2 Fixed in 0.38.2, 0.85.2 Patch available CNA
  • wasmtime (crates.io) Vendor— Affected 0.37.0 to before 0.38.2 Fixed in 0.38.2 Patch available GHSA-5fhj-g3p3-pq9g
  • cranelift-codegen (crates.io) Vendor— Affected 0.84.0 to before 0.85.2 Fixed in 0.85.2 Patch available GHSA-5fhj-g3p3-pq9g

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:bytecodealliance:cranelift-codegen:*:*:*:*:*:rust:*:*0.84.0 to before 0.85.2Vulnerablebytecodealliance
cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*0.37.0 to before 0.38.2Vulnerablebytecodealliance
  • cpe:2.3:a:bytecodealliance:cranelift-codegen:*:*:*:*:*:rust:*:* Versions 0.84.0 to before 0.85.2 Vulnerable ·bytecodealliance
  • cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:* Versions 0.37.0 to before 0.38.2 Vulnerable ·bytecodealliance

Remediation

  • Fix · CNA wasmtime (bytecodealliance) Fixed in 0.38.2, 0.85.2
  • Fix · GHSA-5fhj-g3p3-pq9g wasmtime (crates.io) Fixed in 0.38.2 Advisory →
  • Fix · GHSA-5fhj-g3p3-pq9g cranelift-codegen (crates.io) Fixed in 0.85.2 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-31146
  2. 2026-10-03 Alias added: GHSA-5fhj-g3p3-pq9g

References

Advisory 4

Other 3

  • TI-2023-11636 Guest-controlled out-of-bounds read/write on x86_64 in wasmtime CVSS 3.1CRITICAL 10.0
  • TI-2021-12298 Memory access due to code generation flaw in Cranelift module CVSS 3.1HIGH 8.8
  • TI-2022-13211 Cranelift vulnerable to miscompilation of constant values in division on AArch64 CVSS 3.1HIGH 7.5
  • TI-2022-13148 Miscompilation of `i8x16.swizzle` and `select` with v128 inputs in Wasmtime CVSS 3.1MEDIUM 5.6
  • TI-2023-12205 wasmtime is a fast and secure runtime for WebAssembly. CVSS 3.1MEDIUM 4.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences