Package Instance

Next.js Improper Middleware Redirect Handling Leads to SSRF
A vulnerability in **Next.js Middleware** has been fixed in **v14.2.32** and **v15.4.7**. The issue occurred when request headers were directly passed into `NextResponse.next()`. In self-hosted applications, this could allow Server-Side Request Forgery (SSRF) if certain sensitive headers from the incoming request were reflected back into the response.

All users implementing custom middleware logic in self-hosted environments are strongly encouraged to upgrade and verify correct usage of the `next()` function.

More details at [Vercel Changelog](https://vercel.com/changelog/cve-2025-57822)

Cross-site Scripting
Next.js suffers from XSS via the /_error pages.

Next.js Affected by Cache Key Confusion for Image Optimization API Routes
A vulnerability in Next.js Image Optimization has been fixed in v15.4.5 and v14.2.31. When images returned from API routes vary based on request headers (such as `Cookie` or `Authorization`), these responses could be incorrectly cached and served to unauthorized users due to a cache key confusion bug.

All users are encouraged to upgrade if they use API routes to serve images that depend on request headers and have image optimization enabled.

More details at [Vercel Changelog](https://vercel.com/changelog/cve-2025-57752)

Next.js missing cache-control header may lead to CDN caching empty reply
Next.js before 13.4.20-canary.13 lacks a cache-control header and thus empty prefetch responses may sometimes be cached by a CDN, causing a denial of service to all users requesting the same URL via that CDN.

Next.js Content Injection Vulnerability for Image Optimization
A vulnerability in **Next.js Image Optimization** has been fixed in **v15.4.5** and **v14.2.31**. The issue allowed attacker-controlled external image sources to trigger file downloads with arbitrary content and filenames under specific configurations. This behavior could be abused for phishing or malicious file delivery.

All users relying on `images.domains` or `images.remotePatterns` are encouraged to upgrade and verify that external image sources are strictly validated.

More details at [Vercel Changelog](https://vercel.com/changelog/cve-2025-55173)

Next.js Race Condition to Cache Poisoning
**Summary**  
We received a responsible disclosure from Allam Rachid (zhero) for a low-severity race-condition vulnerability in Next.js. This issue only affects the **Pages Router** under certain misconfigurations, causing normal endpoints to serve `pageProps` data instead of standard HTML.

[Learn more here](https://vercel.com/changelog/cve-2025-32421)

**Credit**  
Thank you to **Allam Rachid (zhero)** for the responsible disclosure. This research was rewarded as part of our bug bounty program.

Directory Traversal in Next.js
### Impact

- **Not affected**: Deployments on ZEIT Now v2 ([https://zeit.co](https://zeit.co/)) are not affected
- **Not affected**: Deployments using the `serverless` target
- **Not affected**: Deployments using `next export`
- **Affected**: Users of Next.js below 9.3.2

We recommend everyone to upgrade regardless of whether you can reproduce the issue or not.

### Patches

https://github.com/zeit/next.js/releases/tag/v9.3.2

### References

https://github.com/zeit/next.js/releases/tag/v9.3.2