{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-47261", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-18T23:03:37.229Z", "datePublished": "2026-06-15T19:47:40.366Z", "dateUpdated": "2026-06-15T19:47:40.366Z"}, "containers": {"cna": {"title": "Wasmtime: WASI path_open(TRUNCATE) bypasses `FilePerms::WRITE` host restriction", "problemTypes": [{"descriptions": [{"cweId": "CWE-284", "lang": "en", "description": "CWE-284: Improper Access Control", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-2r75-cxrj-cmph", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-2r75-cxrj-cmph"}, {"name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v24.0.9", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v24.0.9"}, {"name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.10", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.10"}, {"name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v44.0.2", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v44.0.2"}, {"name": "https://github.com/bytecodealliance/wasmtime/releases/tag/v45.0.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v45.0.0"}], "affected": [{"vendor": "bytecodealliance", "product": "wasmtime", "versions": [{"version": ">= 37.0.0, < 44.0.2", "status": "affected"}, {"version": ">= 25.0.0, < 36.0.10", "status": "affected"}, {"version": "< 24.0.9", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-06-15T19:47:40.366Z"}, "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."}], "source": {"advisory": "GHSA-2r75-cxrj-cmph", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "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."}], "id": "CVE-2026-47261", "lastModified": "2026-06-15T21:17:11.153", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-06-15T21:17:11.153", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v24.0.9"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.10"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v44.0.2"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/releases/tag/v45.0.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-2r75-cxrj-cmph"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-284"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}