{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-115889",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-10-23T19:37:27.176Z",
        "datePublished": "2026-10-23T21:23:27.669Z",
        "dateUpdated": "2026-10-23T21:23:27.669Z"
    },
    "containers": {
        "cna": {
            "title": "Wasmtime: Bit-packing in Cranelift compiler causes silent overflow and miscompilation",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-197",
                            "lang": "en",
                            "description": "CWE-197: Numeric Truncation Error",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-843",
                            "lang": "en",
                            "description": "CWE-843: Access of Resource Using Incompatible Type ('Type Confusion')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 9.9,
                        "baseSeverity": "CRITICAL",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "LOW",
                        "scope": "CHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm"
                },
                {
                    "name": "https://github.com/bytecodealliance/wasmtime/pull/12613",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bytecodealliance/wasmtime/pull/12613"
                },
                {
                    "name": "https://github.com/bytecodealliance/wasmtime/pull/14818",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bytecodealliance/wasmtime/pull/14818"
                },
                {
                    "name": "https://github.com/bytecodealliance/wasmtime/commit/ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bytecodealliance/wasmtime/commit/ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0"
                },
                {
                    "name": "https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa"
                },
                {
                    "name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19"
                },
                {
                    "name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v43.0.0",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v43.0.0"
                }
            ],
            "affected": [
                {
                    "vendor": "bytecodealliance",
                    "product": "wasmtime",
                    "versions": [
                        {
                            "version": "< 36.0.19",
                            "status": "affected"
                        },
                        {
                            "version": ">= 37.0.0, < 43.0.0",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-10-23T21:23:27.669Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "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."
                }
            ],
            "source": {
                "advisory": "GHSA-897f-g5gm-fmxm",
                "discovery": "UNKNOWN"
            }
        }
    }
}