GHSA-wr66-vrwm-5g5x
MEDIUMDenial of Service Vulnerability in next.js
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
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
nextnpmDescription
Impact
Vulnerable code could allow a bad actor to trigger a denial of service attack for anyone running a Next.js app at version >= 12.0.0, and using i18n functionality.
- Affected: All of the following must be true to be affected by this CVE
- Next.js versions above v12.0.0
- Using next start or a custom server
- Using the built-in i18n support
- Not affected:
- Deployments on Vercel (vercel.com) are not affected along with similar environments where invalid requests are filtered before reaching Next.js.
Patches
A patch has been released, [email protected], that mitigates this issue. We recommend all affected users upgrade as soon as possible.
Workarounds
We recommend upgrading whether you can reproduce or not although you can ensure /${locale}/_next/ is blocked from reaching the Next.js instance until you upgrade.
For more information
If you have any questions or comments about this advisory:
- Open an issue in next
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | next | ≥ 12.0.0&&< 12.0.9 | 12.0.9 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for next. 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 next to 12.0.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wr66-vrwm-5g5x 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-wr66-vrwm-5g5x 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-wr66-vrwm-5g5x. 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-wr66-vrwm-5g5x in your dependencies?
O3 detects GHSA-wr66-vrwm-5g5x across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.