GHSA-5h3x-9wvq-w4m2 is a medium-severity (CVSS 5.3) CWE-862 vulnerability in @openzeppelin/contracts. O3 Security confirms whether GHSA-5h3x-9wvq-w4m2 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
OpenZeppelin Contracts's governor proposal creation may be blocked by frontrunning
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
@openzeppelin/contractsnpm@openzeppelin/contracts-upgradeablenpmDescription
Impact
By frontrunning the creation of a proposal, an attacker can become the proposer and gain the ability to cancel it. The attacker can do this repeatedly to try to prevent a proposal from being proposed at all.
This impacts the Governor contract in v4.9.0 only, and the GovernorCompatibilityBravo contract since v4.3.0.
Patches
The problem has been patched in 4.9.1 by introducing opt-in frontrunning protection.
Workarounds
Submit the proposal creation transaction to an endpoint with frontrunning protection.
Credit
Reported by Lior Abadi and Joaquin Pereyra from Coinspect.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @openzeppelin/contracts | ≥ 4.3.0&&< 4.9.1 | 4.9.1 |
| 📦npm | @openzeppelin/contracts-upgradeable | ≥ 4.3.0&&< 4.9.1 | 4.9.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @openzeppelin/contracts. 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 @openzeppelin/contracts to 4.9.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5h3x-9wvq-w4m2 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-5h3x-9wvq-w4m2 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-5h3x-9wvq-w4m2. 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-5h3x-9wvq-w4m2 in your dependencies?
O3 detects GHSA-5h3x-9wvq-w4m2 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.