Changelog

Three Next.js and React vulnerabilities disclosed October 14, 2026 — two critical and one high, covering unauthenticated RCE in use cache functions returning typed arrays, RCE via SVG processing reachable through next/og ImageResponse, and DoS in App Router Server Actions — are patched in 15.5.28 and 16.4.1. Netlify recommends upgrading next and redeploying, and notes that public deploy previews and branch deploys may remain vulnerable until auto-deleted.

Mistral Large 4 is now selectable from the model picker in Netlify Agent Runners, with a 524K-token context window aimed at agentic coding and long-context, multi-step tasks across larger codebases.

TanStack Start apps now deploy on Netlify, with SSR, server routes, server functions, and middleware running on Netlify Functions. A @netlify/vite-plugin-tanstack-start plugin emulates Netlify primitives in the dev server, and new Agent Runners projects default to TanStack Start 1.0.

Google's Gemini 4 Argon model is now available through Netlify's AI Gateway and Agent Runners with zero configuration, so the Google GenAI SDK can be used directly in Netlify Functions without managing API keys or authentication. It is available for all Function types and Agent Runners, with Netlify's caching, rate limiting, and authentication handled automatically.

Meta's Muse Spark and Muse Wonder models are now available through Netlify's AI Gateway with no configuration required, usable via the OpenAI SDK in Functions without managing API keys or authentication. They work in Scheduled, Background, and Edge Functions with Netlify's caching, rate limiting, and authentication applied automatically.

On private projects and sites protected with Netlify team login, Functions and Edge Functions can read the signed-in user from context.user, including their user ID, email address, and access expiry. Because the identity comes from Netlify rather than the request, visitors cannot impersonate another user by sending their own headers.

Claude Haiku 5.5 is now available through Netlify's AI Gateway and Agent Runners with zero configuration, letting the Anthropic SDK be used directly in Netlify Functions without managing API keys or authentication. The model also works across Scheduled Functions, Background Functions, and Edge Functions with automatic access to Netlify's caching, rate limiting, and authentication infrastructure.

Netlify events can now be subscribed to from ChatGPT, covering deploy succeeded, build failed, and form submission events, with automations that respond when they fire. Events pair with the Netlify ChatGPT plugin and Netlify MCP server.

OpenAI's Decisions API is now available through Netlify's AI Gateway with zero configuration, letting the OpenAI SDK in Netlify Functions classify, route, and score inputs without managing API keys. The beta API runs on gpt-6-luna and returns declared choice answers with probabilities and confidence.

Google's Gemini Nano Banana 2.1 image generation model is now callable through Netlify AI Gateway using the model ID gemini-nano-banana-2.1 with the Google Gen AI SDK, without configuring API keys. It is available across Functions, Scheduled Functions, Background Functions, and Edge Functions, with Netlify caching, rate limiting, and authentication applied automatically.

Comments can now be added to individual lines in the diff on the Code tab of Agent Runners, and are sent along with the next prompt so the agent knows which code lines are being referenced. Previously, requesting a fix required describing the location in the prompt by naming the file, quoting code, or explaining which function was meant.

SvelteKit 3 is supported on Netlify from launch, and its upgrade path moves configuration into vite.config.ts, requires Vite 8, and replaces the $lib alias with #lib via Node subpath imports. The migration tool, run with npx sv migrate sveltekit-3, rewrites imports, but #lib directory imports without an explicit file no longer resolve.

TanStack Start's server-function response handling has an unauthenticated reflected cross-site scripting flaw (CVE-2026-102989) where a crafted URL returns attacker-controlled HTML from the app's own origin, letting an attacker run JavaScript in a visitor's session. All applications on affected versions should upgrade to @tanstack/react-start 1.168.60 or later, @tanstack/solid-start 1.168.57 or later, @tanstack/vue-start 1.168.56 or later, and @tanstack/start-server-core 1.169.39 or later.

The security and compliance document library has moved into the Netlify Dashboard, where any signed-in user on any plan can view certifications, the subprocessor list, and public compliance documents from user settings. Sensitive documents such as the SOC 2 report require an access request through the Trust Center, with downloads available after approval.

Next.js 15.5.27 and 16.3.8 fix seven vulnerabilities spanning image optimizer SSRF, cross-route and encoded-path cache poisoning, and information disclosure through metadata image routes and Draft Mode. Netlify users must upgrade Next.js and update the OpenNext adapter to @netlify/plugin-nextjs 5.16.1, since the cross-route cache-poisoning fix changes cache keying and prerendered pages will miss the cache without the adapter update.

OpenAI's GPT-6.1 Sol is available through Netlify's AI Gateway and Agent Runners with no configuration, letting the OpenAI SDK be used directly in Netlify Functions without managing API keys or authentication. It works across Scheduled, Background, and Edge Functions with automatic caching, rate limiting, and authentication.

Sites created with Agent Runners now include Open Graph tags, so shared links show a screenshot, title, and description instead of a bare URL. The tags are on by default for all public Agent Runners sites.

Claude Sonnet 5.5 is now available through Netlify's AI Gateway and Agent Runners with zero configuration, letting you use the Anthropic SDK in Netlify Functions without managing API keys or authentication. It is also available across Background, Scheduled, and Edge Functions with automatic access to Netlify's caching, rate limiting, and authentication infrastructure.

Agent Runners now renders the Deploy Preview inline next to the prompt instead of requiring a separate tab, and the Deploy Preview link remains available. Reviewing an agent's changes and writing the next prompt no longer requires switching views.

An activity feed on the project overview page consolidates production versions, preview versions, and agent runs in one place, with filters for All, Production, Previews, and Agent runs. It is available on all plans and suggests next steps.