GHSA-75jp-vq8x-h4cq
HIGHWasmi Out-of-bounds Write for host to Wasm calls with more than 128 Parameters
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.
Blast Radius
wasmiReal-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
Summary
In the WASMI Interpreter, an Out-of-bounds Buffer Write will arise arise if the host calls or resumes a Wasm function with more parameters than the default limit (128), as it will surpass the stack value. This doesn’t affect calls from Wasm to Wasm, only from host to Wasm.
Impact
After conducting an analysis of the dependent Polkadot systems of wasmi: Pallet Contracts, Parity Signer, and Smoldot, we have found that none on those systems have been affected by the issue as they are calling host to Wasm function with a small limited amount of parameters always.
Mitigations
If you are using wasmi betwen version 0.15.0 and 0.31.0, please update it to the 0.31.1 patch release that we just published.
Workarounds
Ensure no more than 128 parameters can be pass in a call from the host to a Wasm function.
References
Patch PR: <PR>
Special thanks
Special thanks to Stellar Development Foundation for reporting this security vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | wasmi | ≥ 0.15.0&&< 0.31.1 | 0.31.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for wasmi. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update wasmi to 0.31.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-75jp-vq8x-h4cq 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 pinpoints whether GHSA-75jp-vq8x-h4cq is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-75jp-vq8x-h4cq. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-75jp-vq8x-h4cq in your dependencies?
O3 detects GHSA-75jp-vq8x-h4cq across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.