{"cve":"CVE-2026-34944","nvd":{"published":"2026-04-09T19:16:24.187","modified":"2026-10-26T22:10:00.163","status":"Analyzed","description":"Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, On x86-64 platforms with SSE3 disabled Wasmtime's compilation of the f64x2.splat WebAssembly instruction with Cranelift may load 8 more bytes than is necessary. When signals-based-traps are disabled this can result in a uncaught segfault due to loading from unmapped guard pages. With guard pages disabled it's possible for out-of-sandbox data to be loaded, but this data is not visible to WebAssembly guests. This vulnerability is fixed in 24.0.7, 36.0.7, 42.0.2, and 43.0.1.","cvss_v4":{"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":4.1},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H","score":5.7},"cwes":["CWE-248"],"references":["https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-qqfj-4vcm-26hv"],"products":["bytecodealliance:wasmtime"],"source":"nvd","synced_at":"2026-10-26T22:26:44.656832877+00:00"},"epss":{"cve":"CVE-2026-34944","score":0.00227,"percentile":0.13365,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-qqfj-4vcm-26hv","url":"https://osv.dev/vulnerability/GHSA-qqfj-4vcm-26hv","summary":"Wasmtime segfault or unused out-of-sandbox load with `f64x2.splat` operator on x86-64 ","modified":"2026-09-10T03:51:02.990791595Z","packages":[{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":["<24.0.7"],"fixed":["24.0.7"]},{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=25.0.0 <36.0.7"],"fixed":["36.0.7"]},{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=37.0.0 <42.0.2"],"fixed":["42.0.2"]},{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=43.0.0 <43.0.1"],"fixed":["43.0.1"]}]},{"id":"RUSTSEC-2026-0087","url":"https://osv.dev/vulnerability/RUSTSEC-2026-0087","summary":"Wasmtime segfault or unused out-of-sandbox load with `f64x2.splat` operator on Cranelift x86-64","modified":"2026-10-12T18:00:14.305574647Z","packages":[{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=0.0.0-0 <24.0.7",">=25.0.0 <36.0.7",">=37.0.0 <42.0.2",">=43.0.0 <43.0.1"],"fixed":["24.0.7","36.0.7","42.0.2","43.0.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}