https://cve.radiocsirt.org/rss/recent/all/10 Most recent entries from all 2026-10-21T06:56:11.359797+00:00 Vulnerability-Lookup csirt@opendfir.org python-feedgen Contains only the most 10 recent entries. https://cve.radiocsirt.org/vuln/cve-2022-39394 CVE-2022-39394 — wasmtime_trap_code C API function has out of bounds write vulnerability 2026-10-21T06:56:11.361672+00:00

Affected: bytecodealliance wasmtime

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.

 https://cve.radiocsirt.org/vuln/ghsa-h84q-m8rr-3v9q GHSA-h84q-m8rr-3v9q — wasmtime_trap_code C API function has out of bounds write vulnerability 2026-10-21T06:56:11.361769+00:00

Affected: crates.io: wasmtime

### 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/)