# CVE-2025-62711: Wasmtime vulnerable to segfault when using component resources

> A crafted WebAssembly component can crash the Wasmtime host with a segfault, requiring an upgrade to the patched runtime version.

- **Severity:** Low 2.1 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L`)
- **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:** 24 Oct 2025
- **Updated:** 27 Oct 2025
- **Also known as:** GHSA-4h67-722j-5pmc, RUSTSEC-2025-0112, UBUNTU-CVE-2025-62711

## What is CVE-2025-62711?

CVE-2025-62711 is a low-severity denial of service vulnerability in bytecodealliance wasmtime, published on 24 Oct 2025. 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. In versions from 38.0.0 to before 38.0.3, the implementation of component-model related host-to-wasm trampolines in Wasmtime contained a bug where it's possible to carefully craft a component, which when called in a specific way, would crash the host with a segfault or assert failure. Wasmtime 38.0.3 has been released and is patched to fix this issue. There are no workarounds.

Weakness: CWE-755 (Improper Handling of Exceptional Conditions)

## Which versions are affected by CVE-2025-62711?

3 open source packages ship an affected version, including wasmtime. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `wasmtime` | crates.io | From 38.0.0 | 38.0.3 |
| `wasmtime` | crates.io | From 38.0.0 | 38.0.3 |
| `wasmtime` | crates.io | From 38.0.0 | 38.0.3 |

Products: Bytecodealliance Wasmtime.

## How do I fix CVE-2025-62711?

Upgrade wasmtime to 38.0.3 or later.

## Is CVE-2025-62711 being exploited?

There is no known exploitation of CVE-2025-62711 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-2025-62711 and fix it if it is affected.

What it is: CVE-2025-62711 is a low-severity denial of service vulnerability in bytecodealliance wasmtime, published on 24 Oct 2025. 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-2025-62711 in the wild and no public exploit code.

Affected packages and fixed versions:
- wasmtime (crates.io): affected from 38.0.0; fixed in 38.0.3
- wasmtime (crates.io): affected from 38.0.0; fixed in 38.0.3
- wasmtime (crates.io): affected from 38.0.0; fixed in 38.0.3

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-2025-62711/ (Markdown: https://insights.sbomify.com/CVE-2025-62711/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-62711
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-62711
- OSV: https://osv.dev/vulnerability/CVE-2025-62711

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-62711/
Summaries are generated and may contain mistakes; the official description above is the record.