{"id":"UBUNTU-CVE-2026-115889","details":"Wasmtime is a runtime for WebAssembly. Prior to 36.0.19 and 43.0.0, the Cranelift compiler backend bit-packs SSA value indices in a way that can silently overflow in release builds when compiling a sufficiently large or specially crafted Wasm function with many SSA values. The overflow can make Cranelift reference incorrect IR values, causing arbitrary miscompilation, type confusion, and other attacker-controlled effects that may escape the Wasm sandbox on any architecture using the default Cranelift backend. This issue is fixed in versions 36.0.19 and 43.0.0.","modified":"2026-10-27T04:16:51.194874770Z","published":"2026-10-26T00:00:00Z","upstream":["CVE-2026-115889"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-115889"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-115889"},{"type":"REPORT","url":"https://github.com/bytecodealliance/wasmtime/commit/ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0"},{"type":"REPORT","url":"https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa"},{"type":"REPORT","url":"https://github.com/bytecodealliance/wasmtime/pull/12613"},{"type":"REPORT","url":"https://github.com/bytecodealliance/wasmtime/pull/14818"},{"type":"REPORT","url":"https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19"},{"type":"REPORT","url":"https://github.com/bytecodealliance/wasmtime/releases/tag/v43.0.0"},{"type":"REPORT","url":"https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm"}],"affected":[{"package":{"name":"rust-wasmtime","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/rust-wasmtime?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["10.0.1+dfsg-7","15.0.1+dfsg-4","16.0.0+dfsg-2","16.0.0+dfsg-3"],"ecosystem_specific":{"binaries":[{"binary_name":"librust-cranelift-dev","binary_version":"0.103.0+16.0.0+dfsg-3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-115889.json"}},{"package":{"name":"rust-wasmtime","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/rust-wasmtime?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["36.0.5+dfsg-1","36.0.13+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"librust-cranelift-dev","binary_version":"0.123.13+36.0.13+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-115889.json"}},{"package":{"name":"rust-wasmtime","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/rust-wasmtime?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["26.0.1+dfsg-3","26.0.1+dfsg-4","28.0.1+dfsg-3","29.0.1+dfsg-5","36.0.5+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"librust-cranelift-dev","binary_version":"0.123.5+36.0.5+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-115889.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}