CVE-2026-48038
MEDIUMjoi: Uncaught RangeError on deeply nested input through recursive `link()` schemas
Blast Radius
joi📦joiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
joi is a schema description language and data validator for JavaScript. Prior to 17.13.4 and 18.2.1, denial of service is possible via an untrapped exception in services validating user-supplied JSON or object input with recursive link() schemas. When validate() is called without try/catch in a request handler, deeply nested input can trigger an unhandled RangeError and potentially crash the process; lower-impact paths using validateAsync() or try/catch produce a RangeError instead of a structured ValidationError. This issue is fixed in versions 17.13.4 and 18.2.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | joi | ≥ 18.0.0&&< 18.2.1 | 18.2.1 |
| 📦npm | joi | all versions | 17.13.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for joi. 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 joi to 18.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-48038 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 CVE-2026-48038 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 CVE-2026-48038. 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-2026-48038 in your dependencies?
O3 detects CVE-2026-48038 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.