CVE-2022-39394

criticalpriority · track · 39EPSS 0.004 · 29 %ileEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.35% (29th) EPSS
CVSS 9.8 · critical
Is it mine?
6 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · osv · nvd

EPSS · 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.

01

cvss

Technical severity, 0–10. One row per scoring source.

9.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–critical · 3.8–9.8

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9
v3.13.8lowCVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:Lsecondary · ENISA EU
v3.13.8lowCVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:Lsecondary · security-advisories@github.comexploitability 0.3 · impact 3.4
v3.13.8lowCVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:Lsecondary · OSV
v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

04

affected products (6)

Products and version ranges known to be affected.

05

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.

06

also known as (5)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

published 2022-11-10modified 2026-06-17
09

references (8)

External citations — patches, advisories, analysis.

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