{"id":"CVE-2026-115892","state":"PUBLISHED","title":"Wasmtime: Panic lowering a host-created component model stream into a guest that expects a different payload type","description":"Wasmtime is a runtime for WebAssembly. From 46.0.0 until 48.0.7 and 49.0.4, lowering a host-created component-model stream or future into a guest can omit a required payload-type check after the value passes through guest code and returns through StreamAny, FutureAny, Val::Stream, Val::Future, or an equivalent typed reader. A malicious guest that controls exported function types or returned values can cause the host to pass the type-erased value to a guest expecting a different payload type, which panics the Wasmtime host. This issue is fixed in versions 48.0.7 and 49.0.4.","publishedAt":"2026-10-23T21:26:54.528Z","updatedAt":"2026-10-29T14:44:33.323Z","severity":{"score":5.7,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["bytecodealliance wasmtime"],"affected":[{"vendor":"bytecodealliance","product":"wasmtime","versions":[{"version":">= 46.0.0, < 48.0.7","status":"affected"},{"version":">= 49.0.0, < 49.0.4","status":"affected"}]}],"references":["https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-9pvw-hwfg-92h5","https://github.com/bytecodealliance/wasmtime/pull/14819","https://github.com/bytecodealliance/wasmtime/pull/14820","https://github.com/bytecodealliance/wasmtime/pull/14827","https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd","https://github.com/bytecodealliance/wasmtime/commit/48dacc76241f06088e79f3ce1b17642f2f7bf158","https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618","https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7","https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4"],"weaknesses":["CWE-843","CWE-248"],"ingestedAt":"2026-10-29T20:10:43.281Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/115xxx/CVE-2026-115892.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-115892","state":"PUBLISHED","datePublished":"2026-10-23T21:26:54.528Z","dateUpdated":"2026-10-29T14:44:33.323Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-23T19:37:27.176Z"},"containers":{"cna":{"title":"Wasmtime: Panic lowering a host-created component model stream into a guest that expects a different payload type","descriptions":[{"lang":"en","value":"Wasmtime is a runtime for WebAssembly. From 46.0.0 until 48.0.7 and 49.0.4, lowering a host-created component-model stream or future into a guest can omit a required payload-type check after the value passes through guest code and returns through StreamAny, FutureAny, Val::Stream, Val::Future, or an equivalent typed reader. A malicious guest that controls exported function types or returned values can cause the host to pass the type-erased value to a guest expecting a different payload type, which panics the Wasmtime host. This issue is fixed in versions 48.0.7 and 49.0.4."}],"affected":[{"vendor":"bytecodealliance","product":"wasmtime","versions":[{"version":">= 46.0.0, < 48.0.7","status":"affected"},{"version":">= 49.0.0, < 49.0.4","status":"affected"}]}],"references":[{"url":"https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-9pvw-hwfg-92h5","name":"https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-9pvw-hwfg-92h5","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/bytecodealliance/wasmtime/pull/14819","name":"https://github.com/bytecodealliance/wasmtime/pull/14819","tags":["x_refsource_MISC"]},{"url":"https://github.com/bytecodealliance/wasmtime/pull/14820","name":"https://github.com/bytecodealliance/wasmtime/pull/14820","tags":["x_refsource_MISC"]},{"url":"https://github.com/bytecodealliance/wasmtime/pull/14827","name":"https://github.com/bytecodealliance/wasmtime/pull/14827","tags":["x_refsource_MISC"]},{"url":"https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd","name":"https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd","tags":["x_refsource_MISC"]},{"url":"https://github.com/bytecodealliance/wasmtime/commit/48dacc76241f06088e79f3ce1b17642f2f7bf158","name":"https://github.com/bytecodealliance/wasmtime/commit/48dacc76241f06088e79f3ce1b17642f2f7bf158","tags":["x_refsource_MISC"]},{"url":"https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618","name":"https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618","tags":["x_refsource_MISC"]},{"url":"https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7","name":"https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7","tags":["x_refsource_MISC"]},{"url":"https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4","name":"https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"PRESENT","privilegesRequired":"HIGH","userInteraction":"PASSIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":5.7,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-843","lang":"en","description":"CWE-843: Access of Resource Using Incompatible Type ('Type Confusion')","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-248","lang":"en","description":"CWE-248: Uncaught Exception","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-23T21:26:54.528Z"},"source":{"advisory":"GHSA-9pvw-hwfg-92h5","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-29T14:44:25.732629Z","id":"CVE-2026-115892","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-29T14:44:33.323Z"}}]}}}