EUVD-2026-21031

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

CVE-2026-34971

A flaw was found in Wasmtime, a runtime for WebAssembly. On aarch64 systems, a miscompilation bug in Wasmtime's Cranelift backend can be exploited by a guest WebAssembly module. This vulnerability allows the module to bypass memory bounds checks, enabling arbitrary read and write operations on th...

CVE-2026-34988

A flaw was found in Wasmtime, a runtime for WebAssembly. When Wasmtime's pooling allocator is configured with specific settings, it fails to properly reset virtual memory permissions. This oversight allows a malicious WebAssembly instance to read sensitive data from the linear memory of a...

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-2026-34943

A flaw was found in Wasmtime, a runtime for WebAssembly. A malicious guest can exploit an issue where a flags-typed component model value, containing unexpected bit settings, causes the host system to panic during processing. This vulnerability can lead to a Denial of Service DoS, rendering the...

CVE-2026-34942

A flaw was found in Wasmtime, a runtime for WebAssembly. This vulnerability allows a malicious guest to trigger a host panic by improperly verifying the alignment of reallocated strings during transcoding. By transferring specific strings across components, an attacker can exploit this to cause a...

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...

CVE-2026-34987

A flaw was found in Wasmtime, a runtime for WebAssembly. When using its non-default Winch compiler backend, a properly constructed guest WebAssembly Wasm module can exploit an incorrect assumption in how memory offsets are handled. This allows the guest Wasm to access host memory outside its...

EUVD-2026-21039

Wasmtime has out-of-bounds write or crash when transcoding component model strings...

EUVD-2026-21033

Wasmtime has data leakage between pooling allocator instances...

GHSA-6WGR-89RJ-399P Wasmtime has data leakage between pooling allocator instances

Impact Wasmtime's implementation of its pooling allocator contains a bug where in certain configurations the contents of linear memory can be leaked from one instance to the next. The implementation of resetting the virtual memory permissions for linear memory used the wrong predicate to determin...

Wasmtime has data leakage between pooling allocator instances

Impact Wasmtime's implementation of its pooling allocator contains a bug where in certain configurations the contents of linear memory can be leaked from one instance to the next. The implementation of resetting the virtual memory permissions for linear memory used the wrong predicate to determin...

EUVD-2026-21024

Wasmtime has host data leakage with 64-bit tables and Winch...

GHSA-M9W2-8782-2946 Wasmtime has host data leakage with 64-bit tables and Winch

Impact 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 host's stack to WebAssembly guests. The host's stack can possibly contain sensitive...

EUVD-2026-20988

Wasmtime: Heap OOB read in component model UTF-16 to latin1+utf16 string transcoding...

CVE-2026-34988

Wasmtime is a runtime for WebAssembly. From 28.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of its pooling allocator contains a bug where in certain configurations the contents of linear memory can be leaked from one instance to the next. The implementation of resetting the...

DEBIAN-CVE-2026-34988

Wasmtime is a runtime for WebAssembly. From 28.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of its pooling allocator contains a bug where in certain configurations the contents of linear memory can be leaked from one instance to the next. The implementation of resetting the...

CVE-2026-34943

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime contains a possible panic which can happen when a flags-typed component model value is lifted with the Val type. If bits are set outside of the set of flags the component model specifies that these bits...

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...

CVE-2026-34971

Wasmtime is a runtime for WebAssembly. From 32.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Cranelift compilation backend contains a bug on aarch64 when performing a certain shape of heap accesses which means that the wrong address is accessed. When combined with explicit bounds checks a...