CVE-2026-47261— Bytecode Alliance wasmtime 权限许可和访问控制问题漏洞

Wasmtime: WASI path_open(TRUNCATE) bypasses `FilePerms::WRITE` host restriction

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 967–969) 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.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

访问控制不恰当

Bytecode Alliance wasmtime 权限许可和访问控制问题漏洞

bytecodealliance Wasmtime是bytecodealliance组织开源的一个WebAssembly与WASI运行时。 Bytecode Alliance wasmtime 24.0.9之前版本、36.0.10之前版本和44.0.2之前版本存在权限许可和访问控制问题漏洞，该漏洞源于访问控制机制可被绕过，当文件系统预打开指定DirPerms::all()和FilePerms::READ而没有FilePerms::WRITE时，通过wasip2 descriptor.open-at或was

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