CVE-2025-32421 — next
LOWCVE-2025-32421 is a low-severity (CVSS 3.7) CWE-362 vulnerability in next. A fix is available for next — see the affected versions and patch details below.
Next.js Race Condition to Cache Poisoning
Exploitation Status
No confirmed exploitation observed yet
- 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 CVE-2025-32421.
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.
nextnpmDescription
Next.js is a React framework for building full-stack web applications. Versions prior to 14.2.24 and 15.1.6 have a race-condition vulnerability. This issue only affects the Pages Router under certain misconfigurations, causing normal endpoints to serve pageProps data instead of standard HTML. This issue was patched in versions 15.1.6 and 14.2.24 by stripping the x-now-route-matches header from incoming requests. Applications hosted on Vercel's platform are not affected by this issue, as the platform does not cache responses based solely on 200 OK status without explicit cache-control headers. Those who self-host Next.js deployments and are unable to upgrade immediately can mitigate this vulnerability by stripping the x-now-route-matches header from all incoming requests at the content development network and setting cache-control: no-store for all responses under risk. The maintainers of Next.js strongly recommend only caching responses with explicit cache-control headers.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | next | ≥ 0.9.9&&< 14.2.24 | 14.2.24npm install next@14.2.24 |
| 📦npm | next | ≥ 15.0.0&&< 15.1.6 | 15.1.6npm install next@15.1.6 |
Affected Products
next.jsvercelDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for next, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update next to 14.2.24 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-32421 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.
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.
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.Source: Red Hat security advisory for CVE-2025-32421 (CC BY 4.0)
Frequently Asked Questions
Is CVE-2025-32421 in your dependencies?
Find it across npm, including transitive dependencies.