{"id":"CVE-2026-34942","revision":"f6cf784f4c7b4e6ea6dcdef4e77e7c56","records":[{"revision":"f6cf784f4c7b4e6ea6dcdef4e77e7c56","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-34942","aliases":[],"title":"Wasmtime panics when transcoding misaligned utf-16 strings","description":"Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of transcoding strings into the Component Model's utf16 or latin1+utf16 encodings improperly verified the alignment of reallocated strings. This meant that unaligned pointers could be passed to the host for transcoding which would trigger a host panic. This panic is possible to trigger from malicious guests which transfer very specific strings across components with specific addresses. Host panics are considered a DoS vector in Wasmtime as the panic conditions are controlled by the guest in this situation. This vulnerability is fixed in 24.0.7, 36.0.7, 42.0.2, and 43.0.1.","state":0,"publishedAt":"2026-04-09T18:32:56.456+00:00","modifiedAt":"2026-04-09T19:36:13.614+00:00","affected":[{"ecosystem":"Vendor product","name":"wasmtime","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"bytecodealliance\",\n                    \"product\": \"wasmtime\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 24.0.7\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 25.0.0, < 36.0.7\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 37.0.0, < 42.0.2\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 43.0.0, < 44.0.1\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L","score":5.9,"severity":"MEDIUM"}],"references":["https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-jxhv-7h78-9775"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-34942","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-34942","identifiers":["CVE-2026-34942"]},"retained":false,"historicalAffected":[]}],"coverage":[]}