csirt@kutim:~/threat-intel/cve/CVE-2026-34987

Katalog CVE

CVSS 9.9 · Critical EPSS 0,49%

Kerentanan Out-of-bounds Read pada bytecodealliance wasmtime. Skor CVSS 3.1 9.9 (Critical) menurut NVD.

Deskripsi (NVD)

Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime with its Winch (baseline) non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-memory sandbox. This vulnerability requires use of the Winch compiler (-Ccompiler=winch). By default, Wasmtime uses its Cranelift backend, not Winch. With Winch, the same incorrect assumption is present in theory on both aarch64 and x86-64. The aarch64 case has an observed-working proof of concept, while the x86-64 case is theoretical and may not be reachable in practice. This Winch compiler bug can allow the Wasm guest to access memory before or after the linear-memory region, independently of whether pre- or post-guard regions are configured. The accessible range in the initial bug proof-of-concept is up to 32KiB before the start of memory, or ~4GiB after the start of memory, independently of the size of pre- or post-guard regions or the use of explicit or guard-region-based bounds checking. However, the underlying bug assumes a 32-bit memory offset stored in a 64-bit register has its upper bits cleared when it may not, and so closely related variants of the initial proof-of-concept may be able to access truly arbitrary memory in-process. This could result in a host process segmentation fault (DoS), an arbitrary data leak from the host process, or with a write, potentially an arbitrary RCE. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1.

Rincian

Terbit di NVD
9 April 2026
Terakhir diubah
17 Juni 2026
Status NVD
Analyzed
CVSS 3.1
9.9 (Critical), sumber NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-125: Out-of-bounds Read
CWE-787: Out-of-bounds Write
EPSS (30 hari)
0,49% peluang dieksploitasi; lebih tinggi dari 40,4% CVE lain

Produk dan versi terdampak

VendorProdukVersi terdampak
bytecodealliance wasmtime Versi 25.0.0 hingga sebelum 36.0.7
bytecodealliance wasmtime Versi 37.0.0 hingga sebelum 42.0.2
bytecodealliance wasmtime Versi 43.0.0

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:11 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.