GHSA-mm7m-92g8-7m47
Fix: nuxt/nuxt@07e39cdGHSA-mm7m-92g8-7m47 is a CWE-178 vulnerability in nuxt. O3 Security confirms whether GHSA-mm7m-92g8-7m47 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Nuxt: Route-rule middleware bypass via case-sensitivity mismatch between vue-router and the routeRules matcher
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-mm7m-92g8-7m47.
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.
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.
nuxtnpmDescription
Impact
Nuxt looks up routeRules for the current navigation by calling
getRouteRules({ path: to.path }) from the page-router plugin and the
no-pages router plugin. The compiled routeRules matcher (built on
rou3) performs case-sensitive matching, while vue-router is configured
with its default sensitive: false and matches paths case-insensitively.
The two routers therefore disagree on which rules apply to a given
request path: vue-router still matches the page record for
/Admin/dashboard, but the routeRules lookup for the same path
returns no match. Any appMiddleware declared via routeRules is never
added to the middleware set and never runs, on both SSR and client
navigations. The same path skips other path-keyed route rules in the
same way (ssr, redirect, appLayout, and the prerender / payload
hints used client-side).
For applications using routeRules with appMiddleware as an
authorization gate (a documented pattern), an attacker can flip the case
of any static segment in a protected URL (for example /Admin/dashboard
instead of /admin/dashboard) to render the protected page with the
middleware skipped. The server returns the fully server-rendered page
including any useFetch / useAsyncData results captured during SSR.
This is an instance of CWE-178 (Improper Handling of Case Sensitivity)
leading to CWE-863 (Incorrect Authorization) for apps that treat
appMiddleware as an authorization boundary.
Mitigating factors
- Only affects apps that use
routeRules.appMiddleware. The more idiomaticdefinePageMeta({ middleware })is bound to the matched route record and is unaffected. - Nuxt route middleware is documented as an app-layer concern, not a server-side auth boundary; well-built apps enforce authorization again at the API / data-fetching layer.
- Apps that explicitly set
router.options.sensitive = trueare not affected.
Patches
Fixed in [email protected] (commit 07e39cd6) and backported to [email protected] (commit 3f3e3fa7). The fix normalizes the path used for routeRules lookups so it matches vue-router's default case-insensitive semantics.
Workarounds
Until you can upgrade, you can mitigate by either:
- Setting
router.options.sensitive = trueso vue-router matches case-sensitively (this changes route-matching behaviour app-wide). - Moving security-critical middleware off
routeRules.appMiddlewareand ontodefinePageMeta({ middleware: [...] })on the protected page components, which is bound to the matched record. - Enforcing authorization at the API / data-fetching layer (which you should be doing in any case).
Credit
Reported by Anthropic / Claude through Anthropic's coordinated vulnerability disclosure process. Reference: ANT-2026-9FSEBYMC.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | nuxt | ≥ 4.0.0&&< 4.4.7 | 4.4.7 |
| 📦npm | nuxt | ≥ 3.11.0&&< 3.21.7 | 3.21.7 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nuxt. 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 nuxt to 4.4.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mm7m-92g8-7m47 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-mm7m-92g8-7m47 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-mm7m-92g8-7m47. 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-mm7m-92g8-7m47 in your dependencies?
O3 detects GHSA-mm7m-92g8-7m47 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.