RUSTSEC-2026-0313 Outgoing HTTP body write allows guest-driven host memory exhaustion

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-c9gc-w9vx-w86p For more information see the GitHub-hosted security advisory...

RUSTSEC-2026-0316 Dynamic record lifting can allocate beyond the hostcall fuel limit

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-jqpg-j7w6-42pr For more information see the GitHub-hosted security advisory...

RUSTSEC-2026-0315 `call_ref` and exception `catch` can drop some fuel accounting, leading to exponential fuel amplification

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-m63x-6p34-q65x For more information see the GitHub-hosted security advisory...

Dynamic record lifting can allocate beyond the hostcall fuel limit

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-jqpg-j7w6-42pr For more information see the GitHub-hosted security advisory...

Outgoing HTTP body write allows guest-driven host memory exhaustion

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-c9gc-w9vx-w86p For more information see the GitHub-hosted security advisory...

Guest can panic host through filesystem datetime overflow

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-j2g9-4prp-pf6h For more information see the GitHub-hosted security advisory...

`call_ref` and exception `catch` can drop some fuel accounting, leading to exponential fuel amplification

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-m63x-6p34-q65x For more information see the GitHub-hosted security advisory...

CLEANSTART-2026-SI85644 Security fix for GHSA-cq8v-f236-94qc applied in: wasmtime 40.0.0-r0, ztunnel-fips 1.27.8-r3, ztunnel-fips 1.28.5-r1, ztunnel-fips 1.28.7-r0, ztunnel-fips 1.29.1-r1, ztunnel-fips 1.30.0-r0

GHSA-cq8v-f236-94qc affects multiple packages. This issue is resolved in later releases. See references for individual vulnerability details...

CLEANSTART-2026-OG35217 Security fix for CVE-2026-25541 applied in: wasmtime 40.0.0-r0, ztunnel-fips 1.27.8-r4

CVE-2026-25541 affects multiple packages. This issue is resolved in later releases. See references for individual vulnerability details...

wasmtime:wast_tests: Stack-use-after-scope in wast_tests

Project: https://github.com/bytecodealliance/wasmtime.git Detailed Report: https://oss-fuzz.com/testcase?key=6483688326758400 Project: wasmtime Fuzzing Engine: libFuzzer Fuzz Target: wasttests Job Type: libfuzzerasanwasmtime Platform Id: linux Crash Type: Stack-use-after-scope WRITE 7 Crash...

GHSA-3P27-QVP9-27QF Wasmtime has a leak in WASIp1 `fd_renumber` implementation

Impact Wasmtime's native implementation of WASIp1 suffers from a leak in the fdrenumber function where the file descriptor being renumbered to is not properly closed. Wasmtime's implementation erroneously only updated the table of descriptors for WASIp1 and didn't update the underlying table of...

EUVD-2026-41136

Wasmtime has a leak in WASIp1 fdrenumber implementation...

Wasmtime has a leak in WASIp1 `fd_renumber` implementation

Impact Wasmtime's native implementation of WASIp1 suffers from a leak in the fdrenumber function where the file descriptor being renumbered to is not properly closed. Wasmtime's implementation erroneously only updated the table of descriptors for WASIp1 and didn't update the underlying table of...

JLSEC-2026-1356 Wasmtime has a possible panic when lifting `flags` component value

Impact 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 should be ignored but Wasmtime will panic when this value is lifted. This pani...

JLSEC-2026-1365 wasmtime has a panic when allocating a table exceeding the size of the host's address space

Impact Wasmtime's allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables ca...

JLSEC-2026-1362 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...

JLSEC-2026-1350 Wasmtime provides unsound API access to a WebAssembly shared linear memory

Impact Wasmtime's Rust embedder API contains an unsound interaction where a WebAssembly shared linear memory could be viewed as a type which provides safe access to the host Rust to the contents of the linear memory. This is not sound for shared linear memories, which could be modified in paralle...

JLSEC-2026-1357 Wasmtime segfault or unused out-of-sandbox load with `f64x2.splat` operator on x86-64

On x86-64 platforms with SSE3 disabled Wasmtime's compilation of the f64x2.splat 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...

JLSEC-2026-1351 Wasmtime is vulnerable to panic when dropping a `[Typed]Func::call_async` future

The affected versions of Wasmtime can panic if the host embedder drops the future returned by wasmtime::component::TypedFunc::callasync before it resolves. Details Starting with Wasmtime 39.0.0, the component-model-async feature became the default, which brought with it a new implementation of...

JLSEC-2026-1352 Wasmtime WASI implementations are vulnerable to guest-controlled resource exhaustion

Impact Wasmtime's implementation of WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested by the guests. This serves as a Denial of Service vector where a guest can induce a range of...