{"id":"RUSTSEC-2026-0380","revision":null,"records":[{"revision":"39902c0238d24337b217f78efb3490fe","observedAt":"2026-10-23T22:48:20.692+00:00","statement":{"source":"cve-program","id":"CVE-2026-115889","aliases":[],"title":"Wasmtime: Bit-packing in Cranelift compiler causes silent overflow and miscompilation","description":"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.","state":0,"publishedAt":"2026-10-23T21:23:27.669+00:00","modifiedAt":"2026-10-23T21:23:27.669+00:00","affected":[{"ecosystem":"Vendor product","name":"wasmtime","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"bytecodealliance\",\n                    \"product\": \"wasmtime\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 36.0.19\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 37.0.0, < 43.0.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","score":9.9,"severity":"CRITICAL"}],"references":["https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm","https://github.com/bytecodealliance/wasmtime/pull/12613","https://github.com/bytecodealliance/wasmtime/pull/14818","https://github.com/bytecodealliance/wasmtime/commit/ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0","https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa","https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19","https://github.com/bytecodealliance/wasmtime/releases/tag/v43.0.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-115889","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-115889","identifiers":["CVE-2026-115889"]},"retained":false,"historicalAffected":[]},{"revision":"7230189b526d4f6494add28f210d9342","observedAt":"2026-10-25T05:17:25.909+00:00","statement":{"source":"nvd","id":"CVE-2026-115889","aliases":[],"title":"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 Wa…","description":"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.","state":0,"publishedAt":"2026-10-23T22:16:58.4+00:00","modifiedAt":"2026-10-23T22:16:58.55+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","score":9.9,"severity":"CRITICAL"}],"references":["https://github.com/bytecodealliance/wasmtime/commit/ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0","https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa","https://github.com/bytecodealliance/wasmtime/pull/12613","https://github.com/bytecodealliance/wasmtime/pull/14818","https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19","https://github.com/bytecodealliance/wasmtime/releases/tag/v43.0.0","https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-115889","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Deferred","weaknesses":["CWE-197","CWE-843"],"productCriteria":[],"sourceDates":{"published":"2026-10-23T22:16:58.400","lastModified":"2026-10-23T22:16:58.550"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-115889","identifiers":["CVE-2026-115889"]},"retained":false,"historicalAffected":[]},{"revision":"033565308a9d435980ce4368476631ee","observedAt":"2026-10-24T13:19:54.901+00:00","statement":{"source":"osv","id":"GHSA-897f-g5gm-fmxm","aliases":["CVE-2026-115889","RUSTSEC-2026-0380"],"title":"Wasmtime: Bit-packing in Cranelift compiler causes silent overflow and miscompilation","description":"## Summary\n\nIn Wasmtime prior to v43, the Cranelift compiler backend bit-packs its SSA value indices in a way that can result in silent overflow in release builds, and result in incorrect value references in the IR resulting in arbitrary miscompilation. A very large Wasm function body, or one that is specially crafted to use many SSA values, can use this to force type-confusion or other arbitrary side-effects and escape the sandbox.\n\nCranelift was changed in Wasmtime v43 to use a full `u32` index, with checks if that limit is exceeded, and so is no longer susceptible to this bug.\n\n## Impact\n\nA Wasmtime engine with default settings (using the Cranelift backend) on any architecture/platform could experience a sandbox escape from a specially-crafted Wasm module.\n\n## Patches\n\nWasmtime v36.0.19 has been released which fixes this issue.","state":0,"publishedAt":"2026-10-23T22:02:20+00:00","modifiedAt":"2026-10-23T22:25:51.5116598+00:00","affected":[{"ecosystem":"crates.io","name":"wasmtime","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"36.0.19"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"crates.io","name":"wasmtime","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"37.0.0"},{"kind":"fixed","version":"43.0.0"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"CRITICAL"}],"references":["https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm","https://github.com/bytecodealliance/wasmtime/pull/12613","https://github.com/bytecodealliance/wasmtime/pull/14818","https://github.com/bytecodealliance/wasmtime/commit/ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0","https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa","https://github.com/bytecodealliance/wasmtime","https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19","https://github.com/bytecodealliance/wasmtime/releases/tag/v43.0.0","https://rustsec.org/advisories/RUSTSEC-2026-0380.html"],"sourceUrl":"https://github.com/advisories/GHSA-897f-g5gm-fmxm","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-897f-g5gm-fmxm","identifiers":["GHSA-897f-g5gm-fmxm","CVE-2026-115889","RUSTSEC-2026-0380"]},"retained":false,"historicalAffected":[]},{"revision":"a3d3c1da6e754782891cfc6ac8e13ea5","observedAt":"2026-10-24T13:19:54.901+00:00","statement":{"source":"osv","id":"RUSTSEC-2026-0380","aliases":["CVE-2026-115889","GHSA-897f-g5gm-fmxm"],"title":"Bit-packing in Cranelift compiler causes silent overflow and miscompilation","description":"This is an entry in the RustSec database for the Wasmtime security advisory\nlocated at\nhttps://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm\nFor more information see the GitHub-hosted security advisory.","state":0,"publishedAt":"2026-10-19T12:00:00+00:00","modifiedAt":"2026-10-24T06:25:41+00:00","affected":[{"ecosystem":"crates.io","name":"wasmtime","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0.0.0-0"},{"kind":"fixed","version":"36.0.19"},{"kind":"introduced","version":"37.0.0"},{"kind":"fixed","version":"43.0.0"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","score":null,"severity":null}],"references":["https://crates.io/crates/wasmtime","https://rustsec.org/advisories/RUSTSEC-2026-0380.html","https://github.com/bytecodealliance/wasmtime/pull/12613"],"sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0380","license":"OSV · upstream source license applies","key":"osv:RUSTSEC-2026-0380","identifiers":["RUSTSEC-2026-0380","CVE-2026-115889","GHSA-897f-g5gm-fmxm"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-10-25T12:17:13.4615606+00:00","complete":true,"records":1756,"lastAttemptAt":"2026-10-25T12:17:13.4615606+00:00","lastSuccessAt":"2026-10-25T12:17:13.6107042+00:00","error":null,"lastVerifiedAt":"2026-10-25T12:17:13.610705+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-1a687ad2a0b90150aa7d97c9f39e63de695ae2db23e31ebc28df1492c461b23c-87fcc7a2cd473a0a7d7f65ddb8a127d0237422165cdb860c6ef1e7af995757c2","complete":true,"records":413946,"lastAttemptAt":"2026-10-25T12:17:13.1512611+00:00","lastSuccessAt":"2026-10-25T12:17:13.1402122+00:00","error":null,"lastVerifiedAt":"2026-10-25T12:17:13.1512611+00:00","snapshotPublishedAt":"2026-10-25T11:26:44+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-43321610382942b8ad8c85917eab1546","complete":false,"records":4735,"lastAttemptAt":"2026-10-25T12:17:40.6738935+00:00","lastSuccessAt":"2026-10-24T23:18:49.862+00:00","error":"InvalidDataException","lastVerifiedAt":"2026-10-24T23:18:49.862+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":4764,"expectedIdentifiers":13474},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-10-25T12:17:13.4615606+00:00","complete":true,"records":1093,"lastAttemptAt":"2026-10-25T12:17:13.4615606+00:00","lastSuccessAt":"2026-10-25T12:17:13.611487+00:00","error":null,"lastVerifiedAt":"2026-10-25T12:17:13.6114871+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-3198ac6f0bce45c4a01cc0e43c34a327","complete":false,"records":11449,"lastAttemptAt":"2026-10-25T12:17:38.7702857+00:00","lastSuccessAt":"2026-10-25T12:17:38.767+00:00","error":null,"lastVerifiedAt":"2026-10-25T12:17:38.767+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":11500,"expectedIdentifiers":13474},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-2375a4e597279abf92e8747e140fe8da9d421877cd49cae3ac69a2cb78469b2c","complete":true,"records":9779,"lastAttemptAt":"2026-10-25T12:17:13.4139982+00:00","lastSuccessAt":"2026-10-24T13:19:53.1346702+00:00","error":null,"lastVerifiedAt":"2026-10-25T12:17:13.4139982+00:00","snapshotPublishedAt":"2026-10-24T03:03:12+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-16ad89dfea13ab9e9b0108e63a759d63bd4559cc68b58491107d62ee35bbbaf2","complete":true,"records":1965,"lastAttemptAt":"2026-10-25T12:17:13.2026187+00:00","lastSuccessAt":"2026-10-23T16:01:26.4487605+00:00","error":null,"lastVerifiedAt":"2026-10-25T12:17:13.2026187+00:00","snapshotPublishedAt":"2026-10-21T12:18:07+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-7da67a15aa6e56a0e3081a7646dc74d537e6ef974afc593c2b1794ed01970648","complete":true,"records":2969,"lastAttemptAt":"2026-10-25T12:17:13.4280281+00:00","lastSuccessAt":"2026-10-24T13:19:59.1145547+00:00","error":null,"lastVerifiedAt":"2026-10-25T12:17:13.4280281+00:00","snapshotPublishedAt":"2026-10-24T08:47:51+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-d376b9c1142ee0d38c4b9f63e3745e6b549bb9051b75d8a1c9162bf1b72e2d87","complete":true,"records":230757,"lastAttemptAt":"2026-10-25T12:17:13.3054927+00:00","lastSuccessAt":"2026-10-25T11:19:13.609085+00:00","error":null,"lastVerifiedAt":"2026-10-25T12:17:13.3054927+00:00","snapshotPublishedAt":"2026-10-25T10:33:09+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null}]}