GHSA-2HW9-MC66-JC2Q Wasmtime: Preemption and traps during bulk operations enable breaking internal VM state

Impact Wasmtime's implementation of bulk-data-transfer WebAssembly instructions, such as memory.copy, contains a vulnerability when a preemption via epochs or fuel is combined with altering the store's state or cancelling a computation. To prevent these operations from taking too long Wasmtime...

CVE-2026-104855

A flaw was found in wasmtime. Execution preemption checks during bulk operations can expose an invalid intermediate state if an application mutates or continues using the execution store after a cancellation or trap. Under these conditions, an attacker executing WebAssembly code can cause memory...

CVE-2026-104855

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

UBUNTU-CVE-2026-104855

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

CVE-2026-104855

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

CVE-2026-104855 Wasmtime: Preemption and traps during bulk operations enable breaking internal VM state

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

CVE-2026-104855

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

CVE-2026-104855

The Wasmtime runtime (versions 46.0.0 to 46.0.2 and 47.0.3 ) is vulnerable to a flaw where fuel and epoch preemption checks during bulk operations (such as memory.copy, table.grow, and array.copy) can expose invalid intermediate states . If an embedder mutates a Store during a Store::epoch_deadli...

CVE-2026-104855 Wasmtime: Preemption and traps during bulk operations enable breaking internal VM state

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

CVE-2026-104855

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

EUVD-2026-91765

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

CVE-2026-104855 Wasmtime: Preemption and traps during bulk operations enable breaking internal VM state

Wasmtime is a runtime for WebAssembly. From 46.0.0 until 46.0.2 and 47.0.3, fuel and epoch preemption checks inside bulk operations including memory.copy, table.grow, and array.copy can expose invalid intermediate state when an embedder mutates a Store in Store::epochdeadlinecallback or continues...

RUSTSEC-2026-0322 Excessive allocated memory on the host when guests don't have stdio

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-gqmc-89g8-p25r For more information see the GitHub-hosted security advisory...

RUSTSEC-2026-0327 Wasmtime component async-lifted callback result count is unvalidated, causing a native stack buffer overflow

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-32h6-97mm-8q3c For more information see the GitHub-hosted security advisory...

RUSTSEC-2026-0320 Wasmtime wasi:http implementation panics with a zero timeout supplied

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-w4qr-p94g-mjhv For more information see the GitHub-hosted security advisory...

RUSTSEC-2026-0321 WASI preview 0 implementation of `poll_oneoff` circumvents fuel consumption

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-j366-h8gg-77pm For more information see the GitHub-hosted security advisory...

fd_readdir copies uninitialized struct padding into guest memory

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-96f6-r43r-8c24 For more information see the GitHub-hosted security advisory...

Guest can panic host through filesystem timestamp before the epoch on wasip3

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-mr2v-56j5-cmfc For more information see the GitHub-hosted security advisory...

WASI preview 0 implementation of `poll_oneoff` circumvents fuel consumption

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-j366-h8gg-77pm For more information see the GitHub-hosted security advisory...

Wasmtime component async-lifted callback result count is unvalidated, causing a native stack buffer overflow

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-32h6-97mm-8q3c For more information see the GitHub-hosted security advisory...