Vulnerability-Lookup

GHSA-P8XM-42R7-89XG

Vulnerability from github – Published: 2026-05-07 00:08 – Updated: 2026-05-14 20:49

Summary

wasmtime has a panic when allocating a table exceeding the size of the host's address space

Details

Impact

Wasmtime's allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component.

This bug does not affect the pooling allocator which limits tables sizes to much less than the required amount to trigger the overflow. This bug is only present for the on-demand instance allocator, which is Wasmtime's default allocator. This bug also requires the memory64 WebAssembly feature to be enabled, which is on-by-default.

Panicking in the host process is considered a denial-of-service vector for Wasmtime.

Patches

Wasmtime 36.0.8, 43.0.2, and 44.0.1 have all been released which fixes this issue.

Workarounds

Embeddings can switch to using the pooling allocator to work around this issue, or the memory64 WebAssembly proposal can be disabled. Otherwise there is no workaround and users are recommended to upgrade.

Severity

5.9 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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{
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "wasmtime"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "30.0.0"
            },
            {
              "fixed": "36.0.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "wasmtime"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "37.0.0"
            },
            {
              "fixed": "43.0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-44216"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-07T00:08:59Z",
    "nvd_published_at": "2026-05-14T15:16:47Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nWasmtime\u0027s allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component.\n\nThis bug does not affect the pooling allocator which limits tables sizes to much less than the required amount to trigger the overflow. This bug is only present for the on-demand instance allocator, which is Wasmtime\u0027s default allocator. This bug also requires the `memory64` WebAssembly feature to be enabled, which is on-by-default.\n\nPanicking in the host process is considered a denial-of-service vector for Wasmtime.\n\n### Patches\n\nWasmtime 36.0.8, 43.0.2, and 44.0.1 have all been released which fixes this issue.\n\n### Workarounds\n\nEmbeddings can switch to using the pooling allocator to work around this issue, or the `memory64` WebAssembly proposal can be disabled. Otherwise there is no workaround and users are recommended to upgrade.",
  "id": "GHSA-p8xm-42r7-89xg",
  "modified": "2026-05-14T20:49:47Z",
  "published": "2026-05-07T00:08:59Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44216"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/bytecodealliance/wasmtime"
    },
    {
      "type": "WEB",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0114.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "wasmtime has a panic when allocating a table exceeding the size of the host\u0027s address space"
}

CVE-2026-44216 (GCVE-0-2026-44216)

Vulnerability from cvelistv5 – Published: 2026-05-14 14:54 – Updated: 2026-05-15 19:09

Title

Wasmtime: Panic when allocating a table exceeding the size of the host's address space

Summary

Wasmtime is a runtime for WebAssembly. From 30.0.0 to 36.0.8, 43.0.2, and 44.0.1, Wasmtime's allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component. This vulnerability is fixed in 36.0.8, 43.0.2, and 44.0.1.

Severity

5.9 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

GitHub_M

References

1 reference

URL	Tags
https://github.com/bytecodealliance/wasmtime/secu…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version
bytecodealliance	wasmtime	Affected: >= 30.0.0, < 36.0.8 Affected: >= 37.0.0, < 43.0.2 Affected: 44.0.0

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-44216",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-15T19:08:36.553275Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-15T19:09:21.141Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "wasmtime",
          "vendor": "bytecodealliance",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 30.0.0, \u003c 36.0.8"
            },
            {
              "status": "affected",
              "version": "\u003e= 37.0.0, \u003c 43.0.2"
            },
            {
              "status": "affected",
              "version": "44.0.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Wasmtime is a runtime for WebAssembly. From 30.0.0 to 36.0.8, 43.0.2, and 44.0.1, Wasmtime\u0027s allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component. This vulnerability is fixed in 36.0.8, 43.0.2, and 44.0.1."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 5.9,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-770",
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-14T14:54:32.975Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg"
        }
      ],
      "source": {
        "advisory": "GHSA-p8xm-42r7-89xg",
        "discovery": "UNKNOWN"
      },
      "title": "Wasmtime: Panic when allocating a table exceeding the size of the host\u0027s address space"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-44216",
    "datePublished": "2026-05-14T14:54:32.975Z",
    "dateReserved": "2026-05-05T15:13:47.572Z",
    "dateUpdated": "2026-05-15T19:09:21.141Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

rustsec-2026-0114

Vulnerability from osv_rustsec

Published

2026-04-30 12:00

Modified

2026-05-07 08:56

Summary

Panic when allocating a table exceeding the size of the host's address space

Details

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg For more information see the GitHub-hosted security advisory.

Severity

5.9 (Medium)


                    
                      CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

References

URL

Type

	https://crates.io/crates/wasmtime	PACKAGE
	https://rustsec.org/advisories/RUSTSEC-2026-0114.html	ADVISORY
	https://github.com/bytecodealliance/wasmtime/secu…	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "categories": [],
        "cvss": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
        "informational": null
      },
      "ecosystem_specific": {
        "affected_functions": null,
        "affects": {
          "arch": [],
          "functions": [],
          "os": []
        }
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "wasmtime",
        "purl": "pkg:cargo/wasmtime"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "30.0.0"
            },
            {
              "fixed": "36.0.8"
            },
            {
              "introduced": "37.0.0"
            },
            {
              "fixed": "43.0.2"
            },
            {
              "introduced": "44.0.0"
            },
            {
              "fixed": "44.0.1"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "versions": []
    }
  ],
  "aliases": [
    "CVE-2026-44216",
    "GHSA-p8xm-42r7-89xg"
  ],
  "database_specific": {
    "license": "CC0-1.0"
  },
  "details": "This is an entry in the RustSec database for the Wasmtime security advisory\nlocated at\nhttps://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg\nFor more information see the GitHub-hosted security advisory.",
  "id": "RUSTSEC-2026-0114",
  "modified": "2026-05-07T08:56:41Z",
  "published": "2026-04-30T12:00:00Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://crates.io/crates/wasmtime"
    },
    {
      "type": "ADVISORY",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0114.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg"
    }
  ],
  "related": [],
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Panic when allocating a table exceeding the size of the host\u0027s address space"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-P8XM-42R7-89XG

Impact

Patches

Workarounds

CVE-2026-44216 (GCVE-0-2026-44216)

rustsec-2026-0114

Vulnerability from osv_rustsec

Tags

Sightings

Nomenclature