CVE-2026-71321

About vulnerability

Impact

The internal island renderer endpoint (/__nuxt_island/...) decodes and hashes attacker-controlled request input before it validates the URL-resident hash. An unauthenticated POST /__nuxt_island/<name>_<anything>.json with a large JSON body (for example ~4.6 MB / 150k keys) is fully read, destr-parsed, and run through ohash before the request is rejected with a 400. Because Nitro runs on a single event loop, this both wastes CPU on the doomed request and delays every concurrent request. A low request rate is enough to degrade or stall the server. No valid hash and no authentication are required.

Patches

Fixed in [email protected] and [email protected]. The island handler now enforces a raw body-size cap (413) and a JSON nesting-depth cap (400) before parsing or hashing, so oversized or deeply nested input is rejected cheaply.

Workarounds

Put a small request-body limit in front of /__nuxt_island/ at your reverse proxy / edge (islands legitimately send only a compact props payload), or disable server components if unused.

Affected product:

ai-sdk-angular , ai-sdk-assemblyai , ai-sdk-cerebras , ai-sdk-deepgram , ai-sdk-deepinfra , ai-sdk-deepseek , ai-sdk-elevenlabs , ai-sdk-fal , ai-sdk-gateway , ai-sdk-gladia , ai-sdk-harness , ai-sdk-harness-codex , ai-sdk-harness-cursor , ai-sdk-harness-deepagents , ai-sdk-harness-fx , ai-sdk-harness-opencode , ai-sdk-harness-pi , ai-sdk-hume , ai-sdk-langchain , ai-sdk-llamaindex , ai-sdk-lmnt , ai-sdk-luma , ai-sdk-otel , ai-sdk-policy-opa , ai-sdk-replicate , ai-sdk-revai , ai-sdk-rsc , ai-sdk-sandbox-just-bash , ai-sdk-sandbox-vercel , ai-sdk-togetherai , ai-sdk-valibot , ai-sdk-vercel , ai-sdk-workflow , ai-sdk-workflow-harness , nuxt , nuxt-kit , nuxt-nitro-server , nuxt-rspack-builder , nuxt-schema , nuxt-test-utils , nuxt-vite-builder , nuxt-webpack-builder , telemetry , workflow , workflow-ai , workflow-astro , workflow-builders , workflow-cli , workflow-core , workflow-nest , workflow-next , workflow-nuxt , workflow-rollup , workflow-sveltekit , workflow-swc-plugin , workflow-utils , workflow-vite , workflow-vitest , workflow-web , workflow-web-shared , workflow-world , workflow-world-testing , workflow-world-vercel

Affected packages:

nuxt @ 3.12.3 (+850 more)