GHSA-cvj7-5f3c-9vg9 is a high-severity (CVSS 7.5) CWE-190 vulnerability in @chainsafe/lodestar. A fix is available for @chainsafe/lodestar — see the affected versions and patch details below.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@chainsafe/lodestarnpmDescription
Lodestar is a TypeScript implementation of the Ethereum Consensus specification. Prior to version 0.36.0, there is a possible consensus split given maliciously-crafted AttesterSlashing or ProposerSlashing being included on-chain. Because the developers represent uint64 values as native javascript numbers, there is an issue when those variables with large (greater than 2^53) uint64 values are included on chain. In those cases, Lodestar may view valid_AttesterSlashing or ProposerSlashing as invalid, due to rounding errors in large number values. This causes a consensus split, where Lodestar nodes are forked away from the main network. Similarly, Lodestar may consider invalid ProposerSlashing as valid, thus including in proposed blocks that will be considered invalid by the network. Version 0.36.0 contains a fix for this issue. As a workaround, use BigInt to represent Slot and Epoch values in AttesterSlashing and ProposerSlashing objects. BigInt is too slow to be used in all Slot and Epoch cases, so one may carefully use BigInt just where necessary for consensus.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @chainsafe/lodestar | all versions | 0.36.0npm install @chainsafe/lodestar@0.36.0 |
Affected Products
lodestarchainsafeDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @chainsafe/lodestar, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @chainsafe/lodestar to 0.36.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-cvj7-5f3c-9vg9 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.
Frequently Asked Questions
Is GHSA-cvj7-5f3c-9vg9 in your dependencies?
Find it across npm, including transitive dependencies.