CVE-2026-115893 (GCVE-0-2026-115893)

Vulnerability from cvelistv5 – Published: 2026-10-23 21:29 – Updated: 2026-10-23 21:29
VLAI
Title
Wasmtime: Cranelift backend on aarch64 can jump to incorrect target on large Wasm `br_table` instruction
Summary
Wasmtime is a runtime for WebAssembly. Prior to 36.0.19, 48.0.7, and 49.0.4, the Cranelift compiler backend on aarch64 can compile a Wasm br_table instruction with more than approximately 256,000 targets so that it has an incorrect conditional branch target. The branch can then jump to arbitrary other code at a user-controlled offset, allowing a user-controlled Wasm module to escape the sandbox on aarch64 engines using the default Cranelift backend. This issue is fixed in versions 36.0.19, 48.0.7, and 49.0.4.
Severity
9.9 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CWE
  • CWE-691 - Insufficient Control Flow Management
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7793 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
bytecodealliance wasmtime Affected: < 36.0.19
Affected: >= 37.0.0, < 48.0.7
Affected: >= 49.0.0, < 49.0.4
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{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "wasmtime",
          "vendor": "bytecodealliance",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 36.0.19"
            },
            {
              "status": "affected",
              "version": "\u003e= 37.0.0, \u003c 48.0.7"
            },
            {
              "status": "affected",
              "version": "\u003e= 49.0.0, \u003c 49.0.4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Wasmtime is a runtime for WebAssembly. Prior to 36.0.19, 48.0.7, and 49.0.4, the Cranelift compiler backend on aarch64 can compile a Wasm br_table instruction with more than approximately 256,000 targets so that it has an incorrect conditional branch target. The branch can then jump to arbitrary other code at a user-controlled offset, allowing a user-controlled Wasm module to escape the sandbox on aarch64 engines using the default Cranelift backend. This issue is fixed in versions 36.0.19, 48.0.7, and 49.0.4."
        }
      ],
      "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"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-691",
              "description": "CWE-691: Insufficient Control Flow Management",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-23T21:29:33.917Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-mghf-wjfp-p5xm",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-mghf-wjfp-p5xm"
        },
        {
          "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/pull/14819",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/pull/14819"
        },
        {
          "name": "https://github.com/bytecodealliance/wasmtime/pull/14820",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/pull/14820"
        },
        {
          "name": "https://github.com/bytecodealliance/wasmtime/pull/14826",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/pull/14826"
        },
        {
          "name": "https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd"
        },
        {
          "name": "https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618"
        },
        {
          "name": "https://github.com/bytecodealliance/wasmtime/commit/e61df1b454be9313d61a5f8de07722a421139bbe",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/commit/e61df1b454be9313d61a5f8de07722a421139bbe"
        },
        {
          "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/v48.0.7",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7"
        },
        {
          "name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4"
        }
      ],
      "source": {
        "advisory": "GHSA-mghf-wjfp-p5xm",
        "discovery": "UNKNOWN"
      },
      "title": "Wasmtime: Cranelift backend on aarch64 can jump to incorrect target on large Wasm `br_table` instruction"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-115893",
    "datePublished": "2026-10-23T21:29:33.917Z",
    "dateReserved": "2026-10-23T19:37:27.177Z",
    "dateUpdated": "2026-10-23T21:29:33.917Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-115893",
      "date": "2026-10-26",
      "epss": "0.00432",
      "percentile": "0.37299"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "wasmtime",
                "vendor": "bytecodealliance",
                "versions": [
                  {
                    "status": "affected",
                    "version": "\u003c 36.0.19"
                  },
                  {
                    "status": "affected",
                    "version": "\u003e= 37.0.0, \u003c 48.0.7"
                  },
                  {
                    "status": "affected",
                    "version": "\u003e= 49.0.0, \u003c 49.0.4"
                  }
                ]
              }
            ],
            "source": "security-advisories@github.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "Wasmtime is a runtime for WebAssembly. Prior to 36.0.19, 48.0.7, and 49.0.4, the Cranelift compiler backend on aarch64 can compile a Wasm br_table instruction with more than approximately 256,000 targets so that it has an incorrect conditional branch target. The branch can then jump to arbitrary other code at a user-controlled offset, allowing a user-controlled Wasm module to escape the sandbox on aarch64 engines using the default Cranelift backend. This issue is fixed in versions 36.0.19, 48.0.7, and 49.0.4."
          }
        ],
        "id": "CVE-2026-115893",
        "lastModified": "2026-10-23T22:16:58.947",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "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"
              },
              "exploitabilityScore": 3.1,
              "impactScore": 6.0,
              "source": "security-advisories@github.com",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-10-23T22:16:58.820",
        "references": [
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/commit/e61df1b454be9313d61a5f8de07722a421139bbe"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/pull/14818"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/pull/14819"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/pull/14820"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/pull/14826"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-mghf-wjfp-p5xm"
          }
        ],
        "sourceIdentifier": "security-advisories@github.com",
        "vulnStatus": "Deferred",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-691"
              }
            ],
            "source": "security-advisories@github.com",
            "type": "Primary"
          }
        ]
      }
    }
  }
}



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