GHSA-378v-28hj-76wf is a medium-severity (CVSS 5.3) CWE-835 vulnerability in bn.js. A fix is available for bn.js — see the affected versions and patch details below.
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for GHSA-378v-28hj-76wf.
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.
bn.jsnpmDescription
This affects versions of the package bn.js before 4.12.3 and 5.2.3. Calling maskn(0) on any BN instance corrupts the internal state, causing toString(), divmod(), and other methods to enter an infinite loop, hanging the process indefinitely.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | bn.js | all versions | 4.12.3npm install bn.js@4.12.3 |
| 📦npm | bn.js | ≥ 5.0.0&&< 5.2.3 | 5.2.3npm install bn.js@5.2.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for bn.js, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update bn.js to 4.12.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-378v-28hj-76wf is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Frequently Asked Questions
Is GHSA-378v-28hj-76wf in your dependencies?
Find it across npm, including transitive dependencies.