CVE-2026-24116

Wasmtime is a runtime for WebAssembly. Starting in version 29.0.0 and prior to version 36.0.5, 40.0.3, and 41.0.1, on x86-64 platforms with AVX, Wasmtime's compilation of the `f64.copysign` WebAssembly instruction with Cranelift may load 8 more bytes than is necessary. When signals-based-traps are disabled this can result in a uncaught segfault due to loading from unmapped guard pages. With guard pages disabled it's possible for out-of-sandbox data to be loaded, but unless there is another bug in Cranelift this data is not visible to WebAssembly guests. Wasmtime 36.0.5, 40.0.3, and 41.0.1 have been released to fix this issue. Users are recommended to upgrade to the patched versions of Wasmtime. Other affected versions are not patched and users should updated to supported major version instead. This bug can be worked around by enabling signals-based-traps. While disabling guard pages can be a quick fix in some situations, it's not recommended to disabled guard pages as it is a key defense-in-depth measure of Wasmtime.
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*
cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*
cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*

History

17 Jun 2026, 10:22

Type Values Removed Values Added
Summary
  • (es) Wasmtime es un entorno de ejecución para WebAssembly. A partir de la versión 29.0.0 y antes de las versiones 36.0.5, 40.0.3 y 41.0.1, en plataformas x86-64 con AVX, la compilación de Wasmtime de la instrucción WebAssembly f64.copysign con Cranelift puede cargar 8 bytes más de los necesarios. Cuando las trampas basadas en señales están deshabilitadas, esto puede resultar en un segfault no detectado debido a la carga desde páginas de guardia no mapeadas. Con las páginas de guardia deshabilitadas, es posible que se carguen datos fuera de la sandbox, pero a menos que haya otro error en Cranelift, estos datos no son visibles para los invitados de WebAssembly. Wasmtime 36.0.5, 40.0.3 y 41.0.1 han sido lanzadas para solucionar este problema. Se recomienda a los usuarios actualizar a las versiones parcheadas de Wasmtime. Otras versiones afectadas no están parcheadas y los usuarios deberían actualizar a una versión principal compatible en su lugar. Este error se puede eludir habilitando las trampas basadas en señales. Si bien deshabilitar las páginas de guardia puede ser una solución rápida en algunas situaciones, no se recomienda deshabilitar las páginas de guardia, ya que es una medida clave de defensa en profundidad de Wasmtime.

12 Feb 2026, 21:36

Type Values Removed Values Added
References () https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#method.memory_guard_size - () https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#method.memory_guard_size - Product
References () https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#method.signals_based_traps - () https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#method.signals_based_traps - Product
References () https://docs.wasmtime.dev/stability-release.html - () https://docs.wasmtime.dev/stability-release.html - Release Notes
References () https://github.com/bytecodealliance/wasmtime/commit/728fa07184f8da2a046f48ef9b61f869dce133a6 - () https://github.com/bytecodealliance/wasmtime/commit/728fa07184f8da2a046f48ef9b61f869dce133a6 - Patch
References () https://github.com/bytecodealliance/wasmtime/commit/799585fc362fcb991de147dd1a9f2ba0861ed440 - () https://github.com/bytecodealliance/wasmtime/commit/799585fc362fcb991de147dd1a9f2ba0861ed440 - Patch
References () https://github.com/bytecodealliance/wasmtime/commit/ac92d9bb729ad3a6d93f0724c4c33a0c4a9c0227 - () https://github.com/bytecodealliance/wasmtime/commit/ac92d9bb729ad3a6d93f0724c4c33a0c4a9c0227 - Patch
References () https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-vc8c-j3xm-xj73 - () https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-vc8c-j3xm-xj73 - Patch, Vendor Advisory
References () https://rustsec.org/advisories/RUSTSEC-2026-0006.html - () https://rustsec.org/advisories/RUSTSEC-2026-0006.html - Third Party Advisory
First Time Bytecodealliance
Bytecodealliance wasmtime
CPE cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5

27 Jan 2026, 19:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-01-27 19:16

Updated : 2026-06-17 10:22


NVD link : CVE-2026-24116

Mitre link : CVE-2026-24116

CVE.ORG link : CVE-2026-24116


JSON object : View

Products Affected

bytecodealliance

  • wasmtime
CWE
CWE-125

Out-of-bounds Read