Wasmtime with Winch compiler backend on aarch64 may allow a sandbox-escaping memory access

Impact 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...

CVE-2026-34945

A flaw was found in Wasmtime's Winch compiler. This vulnerability, present in versions from 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, arises from an incorrect translation of the table.size instruction for 64-bit WebAssembly tables. An attacker, by crafting a malicious WebAssembly guest, could...

CVE-2026-34946

A flaw was found in Wasmtime, a runtime for WebAssembly Wasm code. A malicious Wasm program, when processed by Wasmtime's Winch compiler, can cause the underlying system to crash. This is due to an error in how the compiler handles certain instructions, leading to a Denial of Service DoS...

GHSA-Q49F-XG75-M9XW Wasmtime has host panic when Winch compiler executes `table.fill`

Impact Wasmtime's Winch compiler contains a vulnerability where the compilation of the table.fill instruction can result in a host panic. This means that a valid guest can be compiled with Winch, on any architecture, and cause the host to panic. This represents a denial-of-service vulnerability i...

Wasmtime has host panic when Winch compiler executes `table.fill`

Impact Wasmtime's Winch compiler contains a vulnerability where the compilation of the table.fill instruction can result in a host panic. This means that a valid guest can be compiled with Winch, on any architecture, and cause the host to panic. This represents a denial-of-service vulnerability i...

DEBIAN-CVE-2026-35186

Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler backend contains a bug where translating the table.grow operator causes the result to be incorrectly typed. For 32-bit tables this means that the result of the operator, internally i...

CVE-2026-34945

Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler contains a bug where a 64-bit table, part of the memory64 proposal of WebAssembly, incorrectly translated the table.size instruction. This bug could lead to disclosing data on the...

UBUNTU-CVE-2026-34945

Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler contains a bug where a 64-bit table, part of the memory64 proposal of WebAssembly, incorrectly translated the table.size instruction. This bug could lead to disclosing data on the...

UBUNTU-CVE-2026-34987

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...

CVE-2026-34987

Wasmtime (WebAssembly runtime) with the Winch baseline compiler backend on aarch64 is vulnerable. From 25.0.0 up to but not including 36.0.7, 42.0.2, and 43.0.1, using -Ccompiler=winch may allow a guest Wasm to access host memory outside the linear-memory sandbox. The aarch64 variant has an obser...

CVE-2026-34946

Summary: Wasmtime’s Winch-based code path can panic the host when compiling the WebAssembly table.fill instruction. From 25.0.0 up to but not including 36.0.7, 42.0.2, and 43.0.1, a historical refactor changed how compiled code references table elements, but Winch paths were not updated, leading ...

CVE-2026-34946 Wasmtime's host panics when Winch compiler executes `table.fill`

Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler contains a vulnerability where the compilation of the table.fill instruction can result in a host panic. This means that a valid guest can be compiled with Winch, on any architecture...

RUSTSEC-2026-0089 Host panic when Winch compiler executes `table.fill`

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-q49f-xg75-m9xw For more information see the GitHub-hosted security advisory...

RUSTSEC-2026-0094 Improperly masked return value from `table.grow` with Winch compiler backend

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-f984-pcp8-v2p7 For more information see the GitHub-hosted security advisory...

Host panic when Winch compiler executes `table.fill`

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-q49f-xg75-m9xw For more information see the GitHub-hosted security advisory...

PT-2026-31686

Name of the Vulnerable Software and Affected Versions Wasmtime versions 25.0.0 through 36.0.6, 42.0.2, and 43.0.1 Description Wasmtime's Winch compiler has a flaw in how it handles the table.size instruction with 64-bit tables, part of the WebAssembly memory64 proposal. This can lead to the...

wasmtime 安全漏洞

Wasmtime is a lightweight WebAssembly runtime open source by the Bytecode Alliance. Versions of Wastime prior to 25.0.0, 36.0.7, 42.0.2, and 43.0.1 contained security vulnerabilities. These vulnerabilities stemmed from the Winch compiler incorrectly translating the table.size instruction, which i...

Linux Distros Unpatched Vulnerability : CVE-2026-34946

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler contains a vulnerability where the compilatio...