Next.js version 15.1.5 introduces a minor update to the popular React framework, building upon the foundation laid by version 15.1.4. While the core dependencies like busboy, postcss, @next/env, styled-jsx, @swc/counter, @swc/helpers, and caniuse-lite remain consistent, the key difference lies within the optional dependencies, specifically the @next/swc packages for various platforms (Darwin x64/arm64, Linux x64 GNU/Musl, and Windows x64/arm64 MSVC). These @next/swc updates likely contain performance improvements, bug fixes, or new features within the Rust-based compiler, impacting build times and potentially runtime performance.
Developers should particularly note the updated releaseDate (2025-01-17T12:47:09.585Z) for 15.1.5 suggests a focused release addressing specific issues or enhancements identified since the previous version (2025-01-07T20:44:51.770Z). Other than the releaseDate itself and the @next/swc packages, the unpackedSize parameter changed slightly implying an adjustment in the code from 120619382 to 119733058. While both versions share a comprehensive set of devDependencies for tasks like linting, testing, and building, indicating a robust development workflow, users upgrading to 15.1.5 should verify compatibility with their existing toolchain and custom configurations. Also good for developers to investigate the "@swc/core" package for potential features or performance boosts. This incremental update signals continued refinement of the Next.js ecosystem, promising a smoother and more efficient development experience.
All the vulnerabilities related to the version 15.1.5 of the package
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.
Credit
Thank you to Allam Rachid (zhero) for the responsible disclosure. This research was rewarded as part of our bug bounty program.
Next.JS vulnerability can lead to DoS via cache poisoning
A vulnerability affecting Next.js has been addressed. It impacted versions 15.0.4 through 15.1.8 and involved a cache poisoning bug leading to a Denial of Service (DoS) condition.
Under certain conditions, this issue may allow a HTTP 204 response to be cached for static pages, leading to the 204 response being served to all users attempting to access the page
More details: CVE-2025-49826
Information exposure in Next.js dev server due to lack of origin verification
A low-severity vulnerability in Next.js has been fixed in version 15.2.2. This issue may have allowed limited source code exposure when the dev server was running with the App Router enabled. The vulnerability only affects local development environments and requires the user to visit a malicious webpage while npm run dev is active.
Because the mitigation is potentially a breaking change for some development setups, to opt-in to the fix, you must configure allowedDevOrigins in your next config after upgrading to a patched version. Learn more.
Learn more: https://vercel.com/changelog/cve-2025-48068
Thanks to sapphi-red and Radman Siddiki for responsibly disclosing this issue.
Authorization Bypass in Next.js Middleware
It is possible to bypass authorization checks within a Next.js application, if the authorization check occurs in middleware.
15.2.314.2.2513.5.912.3.5Note: Next.js deployments hosted on Vercel are automatically protected against this vulnerability.
If patching to a safe version is infeasible, it is recommend that you prevent external user requests which contain the x-middleware-subrequest header from reaching your Next.js application.
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
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
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