Use-after-free via omitted garbage-collector stack maps
Published Jul 20, 2022 · Updated Apr 23, 2025
Use-after-free in Cranelift for Wasmtime 0.37.0 through 0.38.1 allows attackers to corrupt host memory via WebAssembly modules. Alias resolution is omitted from the reference-valued virtual-register input to regalloc2, causing it to treat live references as dead and elide required stack maps. Exploitation requires a host to pass a non-null externref and trigger garbage collection while affected WebAssembly frames remain active.
Summary
What happened
Use-after-free in Cranelift for Wasmtime 0.37.0 through 0.38.1 allows attackers to corrupt host memory via WebAssembly modules. Alias resolution is omitted from the reference-valued virtual-register input to regalloc2, causing it to treat live references as dead and elide required stack maps. Exploitation requires a host to pass a non-null externref and trigger garbage collection while affected WebAssembly frames remain active.
The record
- CVE
- CVE-2022-31146
- Published
- Jul 20, 2022
- Updated
- Apr 23, 2025
- Vendor
- Bytecode Alliance
- Product
- Wasmtime
- Classifications
- CWE-416
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 20, 2022CVE publishedPublication date reported by the CVE source.
- Apr 23, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 0.37.0, < 0.38.2
- Affected versionversion=>= 0.84.0, < 0.85.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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