GHSA-8x6r-g9mw-2r78 — react-router
HIGHGHSA-8x6r-g9mw-2r78 is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in react-router. A fix is available for react-router — see the affected versions and patch details below.
React Router vulnerable to DoS via unbounded path expansion in __manifest endpoint
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.
- 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-8x6r-g9mw-2r78.
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.
How urgent is this, really
GHSA-8x6r-g9mw-2r78 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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.
react-routernpmDescription
React Router is a router for React. In versions 7.0.0 through 7.14.x of react-router and versions 2.10.0 through 2.17.4 of @remix-run/server-runtime, certain crafted requests can consume disproportionate server resources via unbounded path expansion in the __manifest endpoint, resulting in response time degradation and/or service unavailability for end users. This affects React Router Framework Mode applications as well as Remix applications. This does not impact applications using Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>). This is patched in react-router version 7.15.0 and @remix-run/server-runtime version 2.17.5.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | react-router | ≥ 7.0.0&&< 7.15.0 | 7.15.0npm install react-router@7.15.0 |
| 📦npm | @remix-run/server-runtime | ≥ 2.10.0&&< 2.17.5 | 2.17.5npm install @remix-run/server-runtime@2.17.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for react-router, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update react-router to 7.15.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-8x6r-g9mw-2r78 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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-8x6r-g9mw-2r78 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-8x6r-g9mw-2r78. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
A flaw was found in React Router (Framework Mode) and Remix (@remix-run/server-runtime). Crafted requests to the __manifest endpoint can trigger unbounded path expansion, consuming disproportionate server resources and causing denial of service through response time degradation or complete service unavailability. This…
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. Upgrade to a patched version to fully mitigate the issues (ref: https://github.com/remix-run/react-router/security/advisories/GHSA-8x6r-g9mw-2r78).Source: Red Hat security advisory for GHSA-8x6r-g9mw-2r78 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Data Grid 8.6.2 | react-router | RHSA-2026:41951 |
| Red Hat Migration Toolkit for Applications 8.1 | mta/mta-ui-rhel9:1785169013 | RHSA-2026:50300 |
| Red Hat OpenShift AI 3.4 | rhoai/odh-dashboard-rhel9:1787347991 | RHSA-2026:60520 |
| Red Hat Openshift Data Foundation 4.18 | odf4/cephcsi-rhel9:1786705347 | RHSA-2026:56431 |
| Red Hat Openshift Data Foundation 4.19 | odf4/cephcsi-rhel9:1786701839 | RHSA-2026:56366 |
| Red Hat OpenShift Dev Spaces 3.29 | devspaces/dashboard-rhel9:1784737150 | RHSA-2026:48124 |
| Red Hat Trusted Artifact Signer 1.3 | rhtas/rhtas-console-ui-rhel9:1784105894 | RHSA-2026:42085 |
Frequently Asked Questions
Is GHSA-8x6r-g9mw-2r78 in your dependencies?
O3 Security finds GHSA-8x6r-g9mw-2r78 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.