{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-104855", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-10-02T14:38:43.244Z", "datePublished": "2026-10-02T17:37:50.941Z", "dateUpdated": "2026-10-02T17:37:50.941Z"}, "containers": {"cna": {"title": "Wasmtime: Preemption and traps during bulk operations enable breaking internal VM state", "problemTypes": [{"descriptions": [{"cweId": "CWE-362", "lang": "en", "description": "CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')", "type": "CWE"}]}], "metrics": [{"cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "HIGH", "userInteraction": "PASSIVE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "LOW", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 2, "baseSeverity": "LOW", "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N", "version": "4.0"}}], "references": [{"name": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-2hw9-mc66-jc2q", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-2hw9-mc66-jc2q"}, {"name": "https://github.com/bytecodealliance/wasmtime/pull/14041", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/pull/14041"}, {"name": "https://github.com/bytecodealliance/wasmtime/pull/14043", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/pull/14043"}, {"name": "https://github.com/bytecodealliance/wasmtime/pull/14045", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/pull/14045"}, {"name": "https://github.com/bytecodealliance/wasmtime/commit/3ebfbe5af4927c157d6fcaca42b8dbb6d17b73fb", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/commit/3ebfbe5af4927c157d6fcaca42b8dbb6d17b73fb"}, {"name": "https://github.com/bytecodealliance/wasmtime/commit/99b0bc39d447317a4102c056081c83a9a84a46e0", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/commit/99b0bc39d447317a4102c056081c83a9a84a46e0"}, {"name": "https://github.com/bytecodealliance/wasmtime/commit/a3eb27af01ba5a30320a90ea1405059cdfedd353", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/commit/a3eb27af01ba5a30320a90ea1405059cdfedd353"}, {"name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v46.0.2", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v46.0.2"}, {"name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v47.0.3", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v47.0.3"}], "affected": [{"vendor": "bytecodealliance", "product": "wasmtime", "versions": [{"version": ">= 46.0.0, < 46.0.2", "status": "affected"}, {"version": ">= 47.0.0, < 47.0.3", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-10-02T17:37:50.941Z"}, "descriptions": [{"lang": "en", "value": "Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epoch_deadline_callback or continues using a Store after cancellation or a trap. A cancelled non-nullable table growth can leave null elements, linear-memory growth during memory.copy can invalidate retained raw pointers, and callback-triggered garbage collection during array.copy can invalidate GC pointers, resulting in a crash, invalid memory access, or GC heap corruption. Embeddings whose callbacks only access the host data in Store<T>, and embeddings that discard a Store after timeout or epoch deadline, are not affected. This issue is fixed in versions 46.0.2 and 47.0.3."}], "source": {"advisory": "GHSA-2hw9-mc66-jc2q", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "wasmtime", "vendor": "bytecodealliance", "versions": [{"status": "affected", "version": ">= 46.0.0, < 46.0.2"}, {"status": "affected", "version": ">= 47.0.0, < 47.0.3"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epoch_deadline_callback or continues using a Store after cancellation or a trap. A cancelled non-nullable table growth can leave null elements, linear-memory growth during memory.copy can invalidate retained raw pointers, and callback-triggered garbage collection during array.copy can invalidate GC pointers, resulting in a crash, invalid memory access, or GC heap corruption. Embeddings whose callbacks only access the host data in Store<T>, and embeddings that discard a Store after timeout or epoch deadline, are not affected. This issue is fixed in versions 46.0.2 and 47.0.3."}], "id": "CVE-2026-104855", "lastModified": "2026-10-02T18:17:02.220", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 2.0, "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:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:L/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": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-10-02T18:17:02.083", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/commit/3ebfbe5af4927c157d6fcaca42b8dbb6d17b73fb"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/commit/99b0bc39d447317a4102c056081c83a9a84a46e0"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/commit/a3eb27af01ba5a30320a90ea1405059cdfedd353"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/pull/14041"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/pull/14043"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/pull/14045"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v46.0.2"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v47.0.3"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-2hw9-mc66-jc2q"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-362"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{"bugzilla": {"description": "wasmtime: wasmtime: Memory corruption via preemption checks during bulk operations", "id": "2545305", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2545305"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.7", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-1265", "details": ["A flaw was found in wasmtime. Execution preemption checks during bulk operations can expose an invalid intermediate state if an application mutates or continues using the execution store after a cancellation or trap. Under these conditions, an attacker executing WebAssembly code can cause memory corruption, invalid memory access, or an application crash resulting in a Denial of Service (DoS)."], "name": "CVE-2026-104855", "package_state": [{"cpe": "cpe:/a:redhat:connectivity_link:1", "fix_state": "Fix deferred", "package_name": "rhcl-1/wasm-shim-rhel9", "product_name": "Red Hat Connectivity Link 1"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "tree-sitter", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "virt-firmware-rs", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "openshell", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "rust", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-10-02T17:37:50Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-104855\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-104855\nhttps://github.com/bytecodealliance/wasmtime/commit/3ebfbe5af4927c157d6fcaca42b8dbb6d17b73fb\nhttps://github.com/bytecodealliance/wasmtime/commit/99b0bc39d447317a4102c056081c83a9a84a46e0\nhttps://github.com/bytecodealliance/wasmtime/commit/a3eb27af01ba5a30320a90ea1405059cdfedd353\nhttps://github.com/bytecodealliance/wasmtime/pull/14041\nhttps://github.com/bytecodealliance/wasmtime/pull/14043\nhttps://github.com/bytecodealliance/wasmtime/pull/14045\nhttps://github.com/bytecodealliance/wasmtime/releases/tag/v46.0.2\nhttps://github.com/bytecodealliance/wasmtime/releases/tag/v47.0.3\nhttps://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-2hw9-mc66-jc2q"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[46.0.0,46.0.2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[47.0.0,47.0.3)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "wasmtime", "source": "cna", "vendor": "bytecodealliance"}, "product": "wasmtime", "vendor": "bytecodealliance"}], "created": "2026-10-02T19:30:17.011870+00:00", "updated": "2026-10-03T02:00:22.338512+00:00", "vendors": ["bytecodealliance", "bytecodealliance$PRODUCT$wasmtime"]}