{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "0"
                  },
                  {
                    "fixed": "36.0.19"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StringRangeExpression"
              },
              {
                "range": [
                  {
                    "introduced": "37.0.0"
                  },
                  {
                    "fixed": "43.0.0"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StringRangeExpression"
              },
              {
                "range": [
                  {
                    "fixed": "ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "range": [
                  {
                    "fixed": "f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "original_tag": "v36.0.19",
                "range": [
                  {
                    "fixed": "0d6b8ead4e94b0ce76f925611b831b56570aef94"
                  }
                ],
                "source": "REFERENCES_TAG"
              },
              {
                "original_tag": "v43.0.0",
                "range": [
                  {
                    "fixed": "be23469ece57c0be64904f12111c8d808b0ce4ac"
                  }
                ],
                "source": "REFERENCES_TAG"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0d6b8ead4e94b0ce76f925611b831b56570aef94"
            },
            {
              "introduced": "7b3d6ae79e9153a2477668062f5622c10333925f"
            },
            {
              "fixed": "be23469ece57c0be64904f12111c8d808b0ce4ac"
            },
            {
              "fixed": "ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0"
            },
            {
              "fixed": "f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa"
            }
          ],
          "repo": "https://github.com/bytecodealliance/wasmtime",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-897f-g5gm-fmxm"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-197",
      "CWE-843"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/115xxx/CVE-2026-115889.json"
  },
  "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.",
  "id": "CVE-2026-115889",
  "modified": "2026-10-25T02:30:29.237124475Z",
  "published": "2026-10-23T21:23:27.669Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19"
    },
    {
      "type": "WEB",
      "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v43.0.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/115xxx/CVE-2026-115889.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-897f-g5gm-fmxm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-115889"
    },
    {
      "type": "FIX",
      "url": "https://github.com/bytecodealliance/wasmtime/commit/ba8f7d70caa1825b7f64fa75cd9d03f4a438dae0"
    },
    {
      "type": "FIX",
      "url": "https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa"
    },
    {
      "type": "FIX",
      "url": "https://github.com/bytecodealliance/wasmtime/pull/12613"
    },
    {
      "type": "FIX",
      "url": "https://github.com/bytecodealliance/wasmtime/pull/14818"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Wasmtime: Bit-packing in Cranelift compiler causes silent overflow and miscompilation"
}