CVE-2026-94543 Next.js: Cache poisoning of SSG and ISR pages in self-hosted Next.js applications
Attackers can poison the cache of self-hosted Next.js Pages Router applications, causing visitors to receive incorrect content from different routes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-94543?
CVE-2026-94543 is a medium-severity vulnerability in Vercel Next.js, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Next.js is a React framework for building full-stack web applications. From 15.0.0 until 15.5.27 and 16.3.8, self-hosted applications using the Pages Router with statically generated or Incremental Static Regeneration pages can key a response cache entry without sufficiently binding it to the source route. A request can replace one page's cache entry with content from a different route, causing the affected page to serve incorrect content to every visitor until revalidation. Applications deployed on Vercel are not affected. This issue is fixed in versions 15.5.27 and 16.3.8.
Weakness: CWE-524
Which versions are affected by CVE-2026-94543?
4 open source packages ship an affected version, including next. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
next npm | From 15.0.0 | 15.5.27 |
next npm | From 15.0.0 | 15.5.27 |
next npm | From 16.0.0 | 16.3.8 |
next npm | From 16.0.0 | 16.3.8 |
Products include Vercel Next.js.
How do I fix CVE-2026-94543?
Upgrade next to a fixed version for your release line: 15.5.27 or 16.3.8.
Is CVE-2026-94543 being exploited?
There is no known exploitation of CVE-2026-94543 in the wild and no public exploit code.
Other vulnerabilities in Vercel Next.js
- CVE-2025-29927 Authorization Bypass in Next.js Middleware
- CVE-2026-44578 Next.js: Server-side request forgery in applications using WebSocket upgrades
- CVE-2026-94483 Next.js: Server-Side Request Forgery in Image Optimization
- CVE-2026-64642 Next.js: Middleware / Proxy bypass in App Router applications using Turbopack and single locale
- CVE-2026-64645 Next.js: Server-Side Request Forgery in rewrites via attacker-controlled destination hostname
Sources
Also known as CLEANSTART-2026-LV87996, CLEANSTART-2026-QE81238, CLEANSTART-2026-XH75311, CLEANSTART-2026-YH35813, CLSA-2026-1792195721, CLSA-2026-1792196714 and 18 more.