CVE-2026-47261

{"id": "CVE-2026-47261", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-47261", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-06-16T12:45:55.792446Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "bytecodealliance", "product": "wasmtime", "versions": [{"status": "affected", "version": ">= 37.0.0, < 44.0.2"}, {"status": "affected", "version": ">= 25.0.0, < 36.0.10"}, {"status": "affected", "version": "< 24.0.9"}]}]}], "published": "2026-06-15T21:17:11.153", "references": [{"url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v24.0.9", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.10", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v44.0.2", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v45.0.0", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-2r75-cxrj-cmph", "tags": ["Mitigation", "Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-284"}]}, {"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "Wasmtime is a runtime for WebAssembly. In versions prior to 24.0.9, 36.0.10, and 44.0.2, when a filesystem preopen is given DirPerms::all() and FilePerms::READ without FilePerms::WRITE, this access control mechanism can be bypassed via the wasip2 descriptor.open-at or wasip1 path_open interfaces by opening a file with only the OpenFlags::TRUNCATE oflag. The root cause is that the clause handling OpenFlags::TRUNCATE in crates/wasi/src/filesystem.rs (Dir::open_at, lines 967\u2013969) did not set open_mode |= OpenMode::WRITE;, which is later used for the access control check against FilePerms to determine whether opening the file is permitted; the single-line fix adds that missing assignment, after which the affected calls correctly fail with error-code.not-permitted and ERRNO_PERM respectively. Only wasmtime-wasi embeddings that combine DirPerms::MUTATE with FilePerms::READ are affected by this bug. In particular, the Wasmtime project's wasmtime-cli's use of wasmtime-wasi is not affected, because it always sets FilePerms::all() for all preopens. This issue has been fixed in versions 24.0.9, 36.0.10 and44.0.2."}, {"lang": "es", "value": "Wasmtime es un entorno de ejecuci\u00f3n para WebAssembly. En versiones anteriores a la 24.0.9, 36.0.10 y 44.0.2, cuando a una preapertura del sistema de archivos se le otorgan DirPerms::all() y FilePerms::READ sin FilePerms::WRITE, este mecanismo de control de acceso puede ser eludido a trav\u00e9s de las interfaces wasip2 descriptor.open-at o wasip1 path_open abriendo un archivo con solo el indicador OpenFlags::TRUNCATE. La causa ra\u00edz es que la cl\u00e1usula que maneja OpenFlags::TRUNCATE en crates/wasi/src/filesystem.rs (Dir::open_at, l\u00edneas 967-969) no estableci\u00f3 open_mode |= OpenMode::WRITE;, lo cual se usa posteriormente para la verificaci\u00f3n de control de acceso contra FilePerms para determinar si se permite abrir el archivo; la correcci\u00f3n de una sola l\u00ednea a\u00f1ade esa asignaci\u00f3n faltante, despu\u00e9s de lo cual las llamadas afectadas fallan correctamente con error-code.not-permitted y ERRNO_PERM respectivamente. Solo las incrustaciones de wasmtime-wasi que combinan DirPerms::MUTATE con FilePerms::READ se ven afectadas por este error. En particular, el uso de wasmtime-wasi por parte de wasmtime-cli del proyecto Wasmtime no se ve afectado, porque siempre establece FilePerms::all() para todas las preaperturas. Este problema ha sido solucionado en las versiones 24.0.9, 36.0.10 y44.0.2."}], "lastModified": "2026-10-25T23:10:00.167", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*", "vulnerable": true, "matchCriteriaId": "E199A623-C250-4390-88C5-3D3567BE2A3F", "versionEndExcluding": "24.0.9"}, {"criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*", "vulnerable": true, "matchCriteriaId": "C92872A6-C672-43D5-98AB-BB9E5A9D10A5", "versionEndExcluding": "36.0.10", "versionStartIncluding": "25.0.0"}, {"criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*", "vulnerable": true, "matchCriteriaId": "31F391A3-BB50-4827-A6F3-59175BBEB1FD", "versionEndExcluding": "44.0.2", "versionStartIncluding": "37.0.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}