CVE-2023-41880
Miscompilation of wasm `i64x2.shr_s` instruction with constant input on x86_64
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Timeline
ID reserved
By GitHub_M
- 11 days later
· 11 days later
Published
- 13 months later
· 13 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Low2.2 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N |
| NVDNVD · Modified | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.67% · top 48% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 2.2.
Weakness
Affected products
- affected >= 10.0.0, < 10.0.2
- affected >= 11.0.0, < 11.0.2
- affected >= 12.0.0, < 12.0.2
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- crates.iowasmtimeGHSA-gw5p-q8mj-p7gh (opens in a new tab)
References (5)
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-gw5p-q8mj-p7gh (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-gw5p-q8mj-p7gh#:~:text=Mailing%20list%20announcement (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/bytecodealliance/wasmtime/pull/6372 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/bytecodealliance/wasmtime/commit/8d7eda15b0badcbea83a7aac2d08f80788b59240 (opens in a new tab)x_refsource_MISCx_transferred
- https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#method.wasm_simd (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-gw5p-q8mj-p7gh (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2023-41880)Record last updated .