CVE-2023-41880
Description
Wasmtime is a standalone runtime for WebAssembly. Wasmtime versions from 10.0.0 to versions 10.02, 11.0.2, and 12.0.1 contain a miscompilation of the WebAssembly `i64x2.shr_s` instruction on x86_64 platforms when the shift amount is a constant value that is larger than 32. Only x86_64 is affected so all other targets are not affected by this. The miscompilation results in the instruction producing an incorrect result, namely the low 32-bits of the second lane of the vector are derived from the low 32-bits of the second lane of the input vector instead of the high 32-bits. The primary impact of this issue is that any WebAssembly program using the `i64x2.shr_s` with a constant shift amount larger than 32 may produce an incorrect result. This issue is not an escape from the WebAssembly sandbox. Execution of WebAssembly guest programs will still behave correctly with respect to memory sandboxing and isolation from the host. Wasmtime considers non-spec-compliant behavior as a security issue nonetheless. This issue was discovered through fuzzing of Wasmtime's code generator Cranelift. Wasmtime versions 10.0.2, 11.0.2, and 12.0.2 are all patched to no longer have this miscompilation. This issue only affects x86_64 hosts and the only workaround is to either scan for this pattern in wasm modules which is nontrivial or to disable the SIMD proposal for WebAssembly. Users prior to 10.0.0 are unaffected by this vulnerability.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | forky | fixed | 15.0.0+dfsg-1 |
| debian | sid | fixed | 15.0.0+dfsg-1 |
| debian | trixie | fixed | 15.0.0+dfsg-1 |
References
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-gw5p-q8mj-p7gh
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-gw5p-q8mj-p7gh#:~:text=Mailing%20list%20announcement
- https://nvd.nist.gov/vuln/detail/CVE-2023-41880
- https://github.com/bytecodealliance/wasmtime/pull/6372
- https://github.com/bytecodealliance/wasmtime/commit/8d7eda15b0badcbea83a7aac2d08f80788b59240
- https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#method.wasm_simd
- https://github.com/bytecodealliance/wasmtime
- https://rustsec.org/advisories/RUSTSEC-2023-0091.html
- https://crates.io/crates/wasmtime
- https://security-tracker.debian.org/tracker/CVE-2023-41880
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.