CVE-2026-126408

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-126408", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-11-10T21:32:21.765Z", "datePublished": "2026-11-13T09:35:42.943Z", "dateUpdated": "2026-11-13T09:35:42.943Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-11-13T09:35:42.943Z"}, "datePublic": "2026-10-29T00:00:00.000Z", "title": "Wasmtime 47.0.0 before 48.0.8 Denial of Service via TypedFunc Type-Check Panic", "descriptions": [{"lang": "en", "value": "Wasmtime 47.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 contains an insufficient type-check in the TypedFunc embedder API for I31, Option<I31>, and Option<NoneRef> parameter or result types, reaching an unreachable!() path. A malicious guest module exporting a function that uses another anyref-hierarchy type can panic the host embedding, causing denial of service."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Reachable Assertion", "cweId": "CWE-617", "type": "CWE"}]}], "affected": [{"vendor": "bytecodealliance", "product": "wasmtime", "defaultStatus": "unaffected", "packageURL": "pkg:cargo/wasmtime", "versions": [{"version": "47.0.0", "status": "affected", "versionType": "semver", "lessThan": "48.0.8"}, {"version": "48.0.8", "status": "unaffected", "versionType": "semver"}]}, {"vendor": "bytecodealliance", "product": "wasmtime", "defaultStatus": "unaffected", "packageURL": "pkg:cargo/wasmtime", "versions": [{"version": "49.0.0", "status": "affected", "versionType": "semver", "lessThan": "49.0.5"}, {"version": "49.0.5", "status": "unaffected", "versionType": "semver"}]}, {"vendor": "bytecodealliance", "product": "wasmtime", "defaultStatus": "unaffected", "packageURL": "pkg:cargo/wasmtime", "versions": [{"version": "50.0.0", "status": "affected", "versionType": "semver", "lessThan": "50.0.1"}, {"version": "50.0.1", "status": "unaffected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*", "versionStartIncluding": "47.0.0", "versionEndExcluding": "48.0.8"}]}]}, {"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*", "versionStartIncluding": "49.0.0", "versionEndExcluding": "49.0.5"}]}]}, {"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*", "versionStartIncluding": "50.0.0", "versionEndExcluding": "50.0.1"}]}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:A/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N", "attackVector": "ADJACENT", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "HIGH", "userInteraction": "PASSIVE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "LOW", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 1, "baseSeverity": "LOW"}}, {"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:L", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "HIGH", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "LOW", "baseScore": 1.8, "baseSeverity": "LOW"}}], "references": [{"url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-3982-jqvv-277m", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-3982-jqvv-277m)"}, {"name": "VulnCheck Advisory: Wasmtime 47.0.0 before 48.0.8 Denial of Service via TypedFunc Type-Check Panic", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/wasmtime-47.0.0-before-48.0.8-denial-of-service-via-typedfunc-type-check-panic"}], "x_generator": {"engine": "vulncheck-endgame"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "packageURL": "pkg:cargo/wasmtime", "product": "wasmtime", "vendor": "bytecodealliance", "versions": [{"lessThan": "48.0.8", "status": "affected", "version": "47.0.0", "versionType": "semver"}, {"status": "unaffected", "version": "48.0.8", "versionType": "semver"}]}, {"defaultStatus": "unaffected", "packageURL": "pkg:cargo/wasmtime", "product": "wasmtime", "vendor": "bytecodealliance", "versions": [{"lessThan": "49.0.5", "status": "affected", "version": "49.0.0", "versionType": "semver"}, {"status": "unaffected", "version": "49.0.5", "versionType": "semver"}]}, {"defaultStatus": "unaffected", "packageURL": "pkg:cargo/wasmtime", "product": "wasmtime", "vendor": "bytecodealliance", "versions": [{"lessThan": "50.0.1", "status": "affected", "version": "50.0.0", "versionType": "semver"}, {"status": "unaffected", "version": "50.0.1", "versionType": "semver"}]}], "source": "disclosure@vulncheck.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Wasmtime 47.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 contains an insufficient type-check in the TypedFunc embedder API for I31, Option<I31>, and Option<NoneRef> parameter or result types, reaching an unreachable!() path. A malicious guest module exporting a function that uses another anyref-hierarchy type can panic the host embedding, causing denial of service."}], "id": "CVE-2026-126408", "lastModified": "2026-11-13T10:17:45.963", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "ADJACENT_NETWORK", "availabilityImpact": "LOW", "baseScore": 1.8, "baseSeverity": "LOW", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "HIGH", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:A/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:L", "version": "3.1"}, "exploitabilityScore": 0.4, "impactScore": 1.4, "source": "disclosure@vulncheck.com", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "attackVector": "ADJACENT", "availabilityRequirement": "NOT_DEFINED", "baseScore": 1.0, "baseSeverity": "LOW", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "HIGH", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:A/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "LOW", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "disclosure@vulncheck.com", "type": "Secondary"}]}, "published": "2026-11-13T10:17:45.823", "references": [{"source": "disclosure@vulncheck.com", "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-3982-jqvv-277m"}, {"source": "disclosure@vulncheck.com", "url": "https://www.vulncheck.com/advisories/wasmtime-47.0.0-before-48.0.8-denial-of-service-via-typedfunc-type-check-panic"}], "sourceIdentifier": "disclosure@vulncheck.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-617"}], "source": "disclosure@vulncheck.com", "type": "Primary"}]}

{}

{}