CVE-2022-39394
criticalpriority · track · 39EPSS 0.004 · 29 %ileEUUSEPSS · scored 2026-10-27
Wasmtime is a standalone runtime for WebAssembly. Prior to version 2.0.2, there is a bug in Wasmtime's C API implementation where the definition of the `wasmtime_trap_code` does not match its declared signature in the `wasmtime/trap.h` header file. This discrepancy causes the function implementation to perform a 4-byte write into a 1-byte buffer provided by the caller. This can lead to three zero bytes being written beyond the 1-byte location provided by the caller. This bug has been patched and users should upgrade to Wasmtime 2.0.2. This bug can be worked around by providing a 4-byte buffer casted to a 1-byte buffer when calling `wasmtime_trap_code`. Users of the `wasmtime` crate are not affected by this issue, only users of the C API function `wasmtime_trap_code` are affected.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–critical · 3.8–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
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affected products (6)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-h84q-m8rr-3v9qwasmtime_trap_code C API function has out of bounds write vulnerability2024-02-01ghsa · osvUS
### Impact There is a bug in Wasmtime's C API implementation where the definition of the `wasmtime_trap_code` does not match its declared signature in the `wasmtime/trap.h` header file. This discrepancy causes the function implementation to perform a 4-byte write into a 1-byte buffer provided by the caller. This can lead to three zero bytes being written beyond the 1-byte location provided by the caller. ### Patches This bug has been patched and users should upgrade to Wasmtime 2.0.2. ### Workarounds This can be worked around by providing a 4-byte buffer casted to a 1-byte buffer when calling `wasmtime_trap_code`. Users of the `wasmtime` crate are not affected by this issue, only users of the C API function `wasmtime_trap_code` are affected. ### References * [Definition of `wasmtime_trap_code`](https://docs.wasmtime.dev/c-api/trap_8h.html#a6580f4f209d3eaebb6e8b9a901a30b7a) * [Mailing list announcement](https://groups.google.com/a/bytecodealliance.org/g/sec-announce/c/c1HBDDJwNPA) * [Patch to fix for `main` branch](https://github.com/bytecodealliance/wasmtime/commit/5b6d5e78de106503b3b9add218bb3d2b1d63c493) ### For more information If you have any questions or comments about this advisory: * Reach out to us on [the Bytecode Alliance Zulip chat](https://bytecodealliance.zulipchat.com/#narrow/stream/217126-wasmtime) * Open an issue in [the bytecodealliance/wasmtime repository](https://github.com/bytecodealliance/wasmtime/)
- RUSTSEC-2022-0097Out of bounds write in `wasmtime_trap_code` C API function2022-11-07vendor · osvUS
This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-h84q-m8rr-3v9q. For more information see the GitHub-hosted security advisory.
also known as (5)
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sources
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references (8)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2022-39394/cnnvd
- https://github.com/bytecodealliance/wasmtime/commit/087d9d7becf7422b3f872a3bcd5d97bb7ce7ff36cnnvd
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-h84q-m8rr-3v9qcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2022-39394cnnvd
- https://github.com/bytecodealliance/wasmtime/commit/087d9d7becf7422b3f872a3bcd5d97bb7ce7ff36enisa_euvd
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-h84q-m8rr-3v9qenisa_euvd
- https://github.com/bytecodealliance/wasmtime/commit/087d9d7becf7422b3f872a3bcd5d97bb7ce7ff36PatchThird Party Advisorynvd
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-h84q-m8rr-3v9qThird Party Advisorynvd
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