CVE-2025-62711 — wasmtime
Fix: bytecodealliance/wasmtime@192f2fcCVE-2025-62711 is a CWE-755 vulnerability in wasmtime. A fix is available for wasmtime — see the affected versions and patch details below.
Wasmtime vulnerable to segfault when using component resources
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-62711.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
wasmtimeReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | wasmtime | ≥ 38.0.0&&< 38.0.3 | 38.0.3cargo update -p wasmtime --precise 38.0.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for wasmtime, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update wasmtime to 38.0.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-62711 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-62711 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-62711. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-62711 in your dependencies?
O3 Security finds CVE-2025-62711 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.