# CVE-2026-44216: Wasmtime: Panic when allocating a table exceeding the size of the host's address space > An attacker can cause a denial of service by triggering a panic in Wasmtime when allocating an excessively large WebAssembly table. - **Severity:** Medium 5.9 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Over the internet - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 14 May 2026 - **Updated:** 28 Jul 2026 - **Also known as:** DEBIAN-CVE-2026-44216, GHSA-p8xm-42r7-89xg, JLSEC-2026-1365, RUSTSEC-2026-0114, SUSE-SU-2026:22002-1, UBUNTU-CVE-2026-44216, openSUSE-SU-2026:10802-1, openSUSE-SU-2026:20863-1 ## What is CVE-2026-44216? CVE-2026-44216 is a medium-severity denial of service vulnerability in bytecodealliance wasmtime, published on 14 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link. ### Official description Wasmtime is a runtime for WebAssembly. From 30.0.0 to 36.0.8, 43.0.2, and 44.0.1, 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 can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component. This vulnerability is fixed in 36.0.8, 43.0.2, and 44.0.1. Weakness: CWE-190 (Integer Overflow or Wraparound), CWE-770 (Allocation of Resources Without Limits or Throttling) ## Which versions are affected by CVE-2026-44216? 5 open source packages ship an affected version, including wasmtime. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `wasmtime` | crates.io | From 30.0.0 | 36.0.8, 43.0.2, 44.0.1 | | `wasmtime` | crates.io | From 30.0.0 | 36.0.8 | | `wasmtime` | crates.io | From 30.0.0 | 36.0.8 | | `wasmtime` | crates.io | From 37.0.0 | 43.0.2 | | `wasmtime` | crates.io | From 37.0.0 | 43.0.2 | | `tree-sitter` | SUSE:Linux Enterprise Server 16.0 | All versions | 0.26.8-160000.2.1 | | `tree-sitter` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 0.26.8-160000.2.1 | | `tree-sitter` | openSUSE:Tumbleweed | All versions | 0.26.8-3.1 | Products: Bytecodealliance Wasmtime. ## How do I fix CVE-2026-44216? Upgrade wasmtime to a fixed version for your release line: 36.0.8, 43.0.2 or 44.0.1. ## Is CVE-2026-44216 being exploited? There is no known exploitation of CVE-2026-44216 in the wild and no public exploit code. ## Other vulnerabilities in bytecodealliance wasmtime - [CVE-2026-34971](https://insights.sbomify.com/CVE-2026-34971/): Wasmtime miscompiled guest heap access enables sandbox escape on aarch64 Cranelift (critical 9.0) - [CVE-2026-34987](https://insights.sbomify.com/CVE-2026-34987/): Wasmtime with Winch compiler backend on aarch64 may allow a sandbox-escaping memory access (critical 9.0) - [CVE-2022-39393](https://insights.sbomify.com/CVE-2022-39393/): Wasmtime vulnerable to data leakage between instances in the pooling allocator (high 8.6) - [CVE-2022-24791](https://insights.sbomify.com/CVE-2022-24791/): Use after free in Wasmtime (high 8.1) - [CVE-2026-47261](https://insights.sbomify.com/CVE-2026-47261/): Wasmtime: WASI path_open(TRUNCATE) bypasses `FilePerms::WRITE` host restriction (high 7.5) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-44216 and fix it if it is affected. What it is: CVE-2026-44216 is a medium-severity denial of service vulnerability in bytecodealliance wasmtime, published on 14 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2026-44216 in the wild and no public exploit code. Affected packages and fixed versions: - wasmtime (crates.io): affected from 30.0.0; fixed in 36.0.8, 43.0.2, 44.0.1 - wasmtime (crates.io): affected from 30.0.0; fixed in 36.0.8 - wasmtime (crates.io): affected from 30.0.0; fixed in 36.0.8 - wasmtime (crates.io): affected from 37.0.0; fixed in 43.0.2 - wasmtime (crates.io): affected from 37.0.0; fixed in 43.0.2 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-44216/ (Markdown: https://insights.sbomify.com/CVE-2026-44216/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-44216 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-44216 - OSV: https://osv.dev/vulnerability/CVE-2026-44216 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-44216/ Summaries are generated and may contain mistakes; the official description above is the record.